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cleartomark %%EndFont %%BeginFont: CMSY5 %!PS-AdobeFont-1.1: CMSY5 1.0 %%CreationDate: 1991 Aug 15 07:21:16 % Copyright (C) 1997 American Mathematical Society. All Rights Reserved. 11 dict begin /FontInfo 7 dict dup begin /version (1.0) readonly def /Notice (Copyright (C) 1997 American Mathematical Society. All Rights Reserved) readonly def /FullName (CMSY5) readonly def /FamilyName (Computer Modern) readonly def /Weight (Medium) readonly def /ItalicAngle -14.035 def /isFixedPitch false def end readonly def /FontName /CMSY5 def /PaintType 0 def /FontType 1 def /FontMatrix [0.001 0 0 0.001 0 0] readonly def /Encoding 256 array 0 1 255 {1 index exch /.notdef put} for dup 0 /minus put dup 48 /prime put dup 105 /angbracketright put readonly def /FontBBox{21 -944 1448 791}readonly def currentdict end currentfile eexec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cleartomark %%EndFont %%BeginFont: CMSY10 %!PS-AdobeFont-1.1: CMSY10 1.0 %%CreationDate: 1991 Aug 15 07:20:57 % Copyright (C) 1997 American Mathematical Society. All Rights Reserved. 11 dict begin /FontInfo 7 dict dup begin /version (1.0) readonly def /Notice (Copyright (C) 1997 American Mathematical Society. All Rights Reserved) readonly def /FullName (CMSY10) readonly def /FamilyName (Computer Modern) readonly def /Weight (Medium) readonly def /ItalicAngle -14.035 def /isFixedPitch false def end readonly def /FontName /CMSY10 def /PaintType 0 def /FontType 1 def /FontMatrix [0.001 0 0 0.001 0 0] readonly def /Encoding 256 array 0 1 255 {1 index exch /.notdef put} for dup 0 /minus put dup 1 /periodcentered put dup 2 /multiply put dup 6 /plusminus put dup 15 /bullet put dup 17 /equivalence put dup 18 /reflexsubset put dup 20 /lessequal put dup 21 /greaterequal put dup 25 /approxequal put dup 26 /propersubset put dup 28 /lessmuch put dup 29 /greatermuch put dup 32 /arrowleft put dup 33 /arrowright put dup 34 /arrowup put dup 35 /arrowdown put dup 41 /arrowdblright put dup 49 /infinity put dup 50 /element put dup 54 /negationslash put dup 55 /mapsto put dup 76 /L put dup 82 /R put dup 91 /union put dup 102 /braceleft put dup 103 /braceright put dup 106 /bar put dup 107 /bardbl put dup 112 /radical put dup 114 /nabla put dup 120 /section put readonly def /FontBBox{-29 -960 1116 775}readonly def currentdict end currentfile eexec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0000000000000000000000000000000000000000000000000000000000000000 0000000000000000000000000000000000000000000000000000000000000000 0000000000000000000000000000000000000000000000000000000000000000 0000000000000000000000000000000000000000000000000000000000000000 cleartomark %%EndFont %%BeginFont: CMR6 %!PS-AdobeFont-1.1: CMR6 1.0 %%CreationDate: 1991 Aug 20 16:39:02 % Copyright (C) 1997 American Mathematical Society. All Rights Reserved. 11 dict begin /FontInfo 7 dict dup begin /version (1.0) readonly def /Notice (Copyright (C) 1997 American Mathematical Society. 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0000000000000000000000000000000000000000000000000000000000000000 0000000000000000000000000000000000000000000000000000000000000000 0000000000000000000000000000000000000000000000000000000000000000 0000000000000000000000000000000000000000000000000000000000000000 0000000000000000000000000000000000000000000000000000000000000000 0000000000000000000000000000000000000000000000000000000000000000 0000000000000000000000000000000000000000000000000000000000000000 cleartomark %%EndFont %%BeginFont: CMSY6 %!PS-AdobeFont-1.1: CMSY6 1.0 %%CreationDate: 1991 Aug 15 07:21:34 % Copyright (C) 1997 American Mathematical Society. All Rights Reserved. 11 dict begin /FontInfo 7 dict dup begin /version (1.0) readonly def /Notice (Copyright (C) 1997 American Mathematical Society. All Rights Reserved) readonly def /FullName (CMSY6) readonly def /FamilyName (Computer Modern) readonly def /Weight (Medium) readonly def /ItalicAngle -14.035 def /isFixedPitch false def end readonly def /FontName /CMSY6 def /PaintType 0 def /FontType 1 def /FontMatrix [0.001 0 0 0.001 0 0] readonly def /Encoding 256 array 0 1 255 {1 index exch /.notdef put} for dup 0 /minus put readonly def /FontBBox{-4 -948 1329 786}readonly def currentdict end currentfile eexec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cleartomark %%EndFont %%BeginFont: CMMI6 %!PS-AdobeFont-1.1: CMMI6 1.100 %%CreationDate: 1996 Jul 23 07:53:52 % Copyright (C) 1997 American Mathematical Society. All Rights Reserved. 11 dict begin /FontInfo 7 dict dup begin /version (1.100) readonly def /Notice (Copyright (C) 1997 American Mathematical Society. All Rights Reserved) readonly def /FullName (CMMI6) readonly def /FamilyName (Computer Modern) readonly def /Weight (Medium) readonly def /ItalicAngle -14.04 def /isFixedPitch false def end readonly def /FontName /CMMI6 def /PaintType 0 def /FontType 1 def /FontMatrix [0.001 0 0 0.001 0 0] readonly def /Encoding 256 array 0 1 255 {1 index exch /.notdef put} for dup 65 /A put dup 110 /n put readonly def /FontBBox{11 -250 1241 750}readonly def currentdict end currentfile eexec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cleartomark %%EndFont %%BeginFont: CMSY8 %!PS-AdobeFont-1.1: CMSY8 1.0 %%CreationDate: 1991 Aug 15 07:22:10 % Copyright (C) 1997 American Mathematical Society. All Rights Reserved. 11 dict begin /FontInfo 7 dict dup begin /version (1.0) readonly def /Notice (Copyright (C) 1997 American Mathematical Society. All Rights Reserved) readonly def /FullName (CMSY8) readonly def /FamilyName (Computer Modern) readonly def /Weight (Medium) readonly def /ItalicAngle -14.035 def /isFixedPitch false def end readonly def /FontName /CMSY8 def /PaintType 0 def /FontType 1 def /FontMatrix [0.001 0 0 0.001 0 0] readonly def /Encoding 256 array 0 1 255 {1 index exch /.notdef put} for dup 0 /minus put dup 6 /plusminus put dup 25 /approxequal put dup 49 /infinity put dup 120 /section put readonly def /FontBBox{-30 -955 1185 779}readonly def currentdict end currentfile eexec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cleartomark %%EndFont %%BeginFont: CMMI8 %!PS-AdobeFont-1.1: CMMI8 1.100 %%CreationDate: 1996 Jul 23 07:53:54 % Copyright (C) 1997 American Mathematical Society. All Rights Reserved. 11 dict begin /FontInfo 7 dict dup begin /version (1.100) readonly def /Notice (Copyright (C) 1997 American Mathematical Society. All Rights Reserved) readonly def /FullName (CMMI8) readonly def /FamilyName (Computer Modern) readonly def /Weight (Medium) readonly def /ItalicAngle -14.04 def /isFixedPitch false def end readonly def /FontName /CMMI8 def /PaintType 0 def /FontType 1 def /FontMatrix [0.001 0 0 0.001 0 0] readonly def /Encoding 256 array 0 1 255 {1 index exch /.notdef put} for dup 33 /omega put dup 34 /epsilon put dup 68 /D put dup 73 /I put dup 76 /L put dup 77 /M put dup 80 /P put dup 85 /U put dup 105 /i put dup 107 /k put dup 119 /w put dup 120 /x put readonly def /FontBBox{-24 -250 1110 750}readonly def currentdict end currentfile eexec D9D66F633B846A97B686A97E45A3D0AA0529731C99A784CCBE85B4993B2EEBDE 3B12D472B7CF54651EF21185116A69AB1096ED4BAD2F646635E019B6417CC77B 532F85D811C70D1429A19A5307EF63EB5C5E02C89FC6C20F6D9D89E7D91FE470 B72BEFDA23F5DF76BE05AF4CE93137A219ED8A04A9D7D6FDF37E6B7FCDE0D90B 986423E5960A5D9FBB4C956556E8DF90CBFAEC476FA36FD9A5C8175C9AF513FE 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0000000000000000000000000000000000000000000000000000000000000000 0000000000000000000000000000000000000000000000000000000000000000 0000000000000000000000000000000000000000000000000000000000000000 0000000000000000000000000000000000000000000000000000000000000000 0000000000000000000000000000000000000000000000000000000000000000 0000000000000000000000000000000000000000000000000000000000000000 0000000000000000000000000000000000000000000000000000000000000000 0000000000000000000000000000000000000000000000000000000000000000 cleartomark %%EndFont %%BeginFont: CMR8 %!PS-AdobeFont-1.1: CMR8 1.0 %%CreationDate: 1991 Aug 20 16:39:40 % Copyright (C) 1997 American Mathematical Society. All Rights Reserved. 11 dict begin /FontInfo 7 dict dup begin /version (1.0) readonly def /Notice (Copyright (C) 1997 American Mathematical Society. All Rights Reserved) readonly def /FullName (CMR8) readonly def /FamilyName (Computer Modern) readonly def /Weight (Medium) readonly def /ItalicAngle 0 def /isFixedPitch false def end readonly def /FontName /CMR8 def /PaintType 0 def /FontType 1 def /FontMatrix [0.001 0 0 0.001 0 0] readonly def /Encoding 256 array 0 1 255 {1 index exch /.notdef put} for dup 40 /parenleft put dup 41 /parenright put dup 43 /plus put dup 48 /zero put dup 49 /one put dup 50 /two put dup 61 /equal put readonly def /FontBBox{-36 -250 1070 750}readonly def currentdict end currentfile eexec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cleartomark %%EndFont %%BeginFont: CMMI5 %!PS-AdobeFont-1.1: CMMI5 1.100 %%CreationDate: 1996 Aug 02 08:21:10 % Copyright (C) 1997 American Mathematical Society. All Rights Reserved. 11 dict begin /FontInfo 7 dict dup begin /version (1.100) readonly def /Notice (Copyright (C) 1997 American Mathematical Society. All Rights Reserved) readonly def /FullName (CMMI5) readonly def /FamilyName (Computer Modern) readonly def /Weight (Medium) readonly def /ItalicAngle -14.04 def /isFixedPitch false def end readonly def /FontName /CMMI5 def /PaintType 0 def /FontType 1 def /FontMatrix [0.001 0 0 0.001 0 0] readonly def /Encoding 256 array 0 1 255 {1 index exch /.notdef put} for dup 61 /slash put dup 84 /T put dup 105 /i put dup 107 /k put readonly def /FontBBox{37 -250 1349 750}readonly def currentdict end currentfile eexec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cleartomark %%EndFont %%BeginFont: CMR5 %!PS-AdobeFont-1.1: CMR5 1.00B %%CreationDate: 1992 Feb 19 19:55:02 % Copyright (C) 1997 American Mathematical Society. All Rights Reserved. 11 dict begin /FontInfo 7 dict dup begin /version (1.00B) readonly def /Notice (Copyright (C) 1997 American Mathematical Society. All Rights Reserved) readonly def /FullName (CMR5) readonly def /FamilyName (Computer Modern) readonly def /Weight (Medium) readonly def /ItalicAngle 0 def /isFixedPitch false def end readonly def /FontName /CMR5 def /PaintType 0 def /FontType 1 def /FontMatrix [0.001 0 0 0.001 0 0] readonly def /Encoding 256 array 0 1 255 {1 index exch /.notdef put} for dup 49 /one put dup 50 /two put dup 111 /o put dup 112 /p put dup 116 /t put readonly def /FontBBox{-341 -250 1304 965}readonly def currentdict end currentfile eexec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cleartomark %%EndFont %%BeginFont: CMEX10 %!PS-AdobeFont-1.1: CMEX10 1.00 %%CreationDate: 1992 Jul 23 21:22:48 % Copyright (C) 1997 American Mathematical Society. All Rights Reserved. 11 dict begin /FontInfo 7 dict dup begin /version (1.00) readonly def /Notice (Copyright (C) 1997 American Mathematical Society. All Rights Reserved) readonly def /FullName (CMEX10) readonly def /FamilyName (Computer Modern) readonly def /Weight (Medium) readonly def /ItalicAngle 0 def /isFixedPitch false def end readonly def /FontName /CMEX10 def /PaintType 0 def /FontType 1 def /FontMatrix [0.001 0 0 0.001 0 0] readonly def /Encoding 256 array 0 1 255 {1 index exch /.notdef put} for dup 18 /parenleftbigg put dup 19 /parenrightbigg put dup 20 /bracketleftbigg put dup 21 /bracketrightbigg put dup 26 /braceleftbigg put dup 32 /parenleftBigg put dup 33 /parenrightBigg put dup 48 /parenlefttp put dup 49 /parenrighttp put dup 50 /bracketlefttp put dup 51 /bracketrighttp put dup 52 /bracketleftbt put dup 53 /bracketrightbt put dup 54 /bracketleftex put dup 55 /bracketrightex put dup 56 /bracelefttp put dup 58 /braceleftbt put dup 60 /braceleftmid put dup 62 /braceex put dup 64 /parenleftbt put dup 65 /parenrightbt put dup 66 /parenleftex put dup 67 /parenrightex put dup 80 /summationtext put dup 83 /uniontext put dup 88 /summationdisplay put dup 112 /radicalbig put readonly def /FontBBox{-24 -2960 1454 772}readonly def currentdict end currentfile eexec D9D66F633B846A97B686A97E45A3D0AA052A014267B7904EB3C0D3BD0B83D891 016CA6CA4B712ADEB258FAAB9A130EE605E61F77FC1B738ABC7C51CD46EF8171 9098D5FEE67660E69A7AB91B58F29A4D79E57022F783EB0FBBB6D4F4EC35014F D2DECBA99459A4C59DF0C6EBA150284454E707DC2100C15B76B4C19B84363758 469A6C558785B226332152109871A9883487DD7710949204DDCF837E6A8708B8 2BDBF16FBC7512FAA308A093FE5CF5B8CAC6A7BEB5D02276E511FFAF2AE11910 DE076F24311D94D07CACC323F360887F1EA11BDDA7927FF3325986FDB0ABDFC8 8E4B40E7988921D551EC0867EBCA44C05657F0DC913E7B3004A5F3E1337B6987 FEBC45F989C8DC6DC0AD577E903F05D0D54208A0AE7F28C734F130C133B48422 BED48639A2B74E4C08F2E710E24A99F347E0F4394CE64EACB549576E89044E52 EABE595BC964156D9D8C2BAB0F49664E951D7C1A3D1789C47F03C7051A63D5E8 DF04FAAC47351E82CAE0794AA9692C6452688A74A7A6A7AD09B8A9783C235EC1 EA2156261B8FB331827145DE315B6EC1B3D8B67B3323F761EAF4C223BB214C4C 6B062D1B281F5041D068319F4911058376D8EFBA59884BA3318C5BC95684F281 E0591BC0D1B2A4592A137FF301610019B8AC46AE6E48BC091E888E4487688350 E9AD5074EE4848271CE4ACC38D8CBC8F3DB32813DDD5B341AF9A6601281ABA38 4A978B98483A63FCC458D0E3BCE6FD830E7E09B0DB987A6B63B74638FC9F21A5 8C68479E1A85225670D79CDDE5AC0B77F5A994CA700B5F0FF1F97FC63EFDE023 8135F04A9D20C31998B12AE06676C362141AAAA395CDEF0A49E0141D335965F2 FB4198499799CECCC8AA5D255264784CD30A3E8295888EFBC2060ADDD7BAC45A EEEECDFF7A47A88E69D84C9E572616C1AC69A34B5F0D0DE8EE4EDF9F4ADE0387 680924D8D5B73EF04EAD7F45977CA8AD73D4DD45DE1966A3B8251C0386164C35 5880DD2609C80E96D1AB861C9259748E98F6711D4E241A269ED51FF328344664 3AF9F18DCE671611DB2F5D3EA77EE734D2BED623F973E6840B8DAD1E2C3C2666 DD4DD1C1C820F145FDBF9754AEA3845BE3798BEC3392AADD5B37C8B1BAB2626C A4B87143B6054D3AA2D05633DB6E0639310A2DDC4D3244F7F072A8D61F0B3709 C95E1F60D1114661182BFA8D5AF65FB0DAB26C1CCEA507F3B3C5649AC2AB3558 2F97490CC9CAC0F7E74001E83AB614A34B1F2AFEAD4BDE35964931BCAC2FE643 0EBE6C925E8CC3F5A9E4A0D5A337816CC39FC44AD169272FC974ABFBF053735D 040262E3C23A3E7F6AD072F0C43605DF4A0809E7615676617EF309E0856F689F CD1029F0058EA85257DB7E3D5D4722CD8AFC8371D3C48A8A2CBFA264259B97AB 4048A4B67450C98DE105337A9F1F776DE911D33360754208C0180289302EB52D 5179DA748A197C1FCF377093739CDAB256C6FEF9D7E677607821FDE8ECB71074 D946E4B525E6B6B786F3784F0E09C7280D4685E81671E96ACFA00F4DD5153513 E15A276A527C5B3505DEC97937CA7A7108614270461603ACE1BCE534E6E27D3C 79BA1F7B097918FE92D89FE6FD6D4E713B4C70B729FDEDA0D5221A50020BF0C2 10141AE39513E39E1827B3C2E9361E8094A5AB92D0F55965C6BA5E55B06FC34D C844B9274296C9645091FC8E98E1993E019199C9CA43AC05B7730FC61D035D46 06FFBE657BD3822324740233DF004007F247EC3E08AE3AE6FB041325FF80AE5F FB2395C907A222C5819FB162674C53153EF6DFF4AC9EA6D796C25AA9FCDF7FF5 AD25F15A0720AD18C75E8361B8B92FC7398B8823647E4B63F1B42279ECFAABC7 63227BAEE6C2E81D1F8903167C8D560998C5490499FFB1B7EE27B97C691696C0 9B089494374C8EAA30AE440E501590DECF23B389C31E480ACDECE5BB86554FA4 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0000000000000000000000000000000000000000000000000000000000000000 0000000000000000000000000000000000000000000000000000000000000000 0000000000000000000000000000000000000000000000000000000000000000 0000000000000000000000000000000000000000000000000000000000000000 0000000000000000000000000000000000000000000000000000000000000000 0000000000000000000000000000000000000000000000000000000000000000 cleartomark %%EndFont %%BeginFont: CMR10 %!PS-AdobeFont-1.1: CMR10 1.00B %%CreationDate: 1992 Feb 19 19:54:52 % Copyright (C) 1997 American Mathematical Society. All Rights Reserved. 11 dict begin /FontInfo 7 dict dup begin /version (1.00B) readonly def /Notice (Copyright (C) 1997 American Mathematical Society. All Rights Reserved) readonly def /FullName (CMR10) readonly def /FamilyName (Computer Modern) readonly def /Weight (Medium) readonly def /ItalicAngle 0 def /isFixedPitch false def end readonly def /FontName /CMR10 def /PaintType 0 def /FontType 1 def /FontMatrix [0.001 0 0 0.001 0 0] readonly def /Encoding 256 array 0 1 255 {1 index exch /.notdef put} for dup 1 /Delta put dup 3 /Lambda put dup 10 /Omega put dup 12 /fi put dup 22 /macron put dup 40 /parenleft put dup 41 /parenright put dup 43 /plus put dup 48 /zero put dup 49 /one put dup 50 /two put dup 51 /three put dup 52 /four put dup 53 /five put dup 54 /six put dup 55 /seven put dup 56 /eight put dup 57 /nine put dup 58 /colon put dup 59 /semicolon put dup 61 /equal put dup 91 /bracketleft put dup 93 /bracketright put dup 94 /circumflex put dup 97 /a put dup 100 /d put dup 103 /g put dup 105 /i put dup 108 /l put dup 109 /m put dup 110 /n put dup 111 /o put dup 112 /p put dup 115 /s put dup 120 /x put dup 126 /tilde put readonly 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All Rights Reserved. 11 dict begin /FontInfo 7 dict dup begin /version (1.0) readonly def /Notice (Copyright (C) 1997 American Mathematical Society. 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0000000000000000000000000000000000000000000000000000000000000000 0000000000000000000000000000000000000000000000000000000000000000 0000000000000000000000000000000000000000000000000000000000000000 0000000000000000000000000000000000000000000000000000000000000000 0000000000000000000000000000000000000000000000000000000000000000 0000000000000000000000000000000000000000000000000000000000000000 cleartomark %%EndFont %%BeginFont: CMSY7 %!PS-AdobeFont-1.1: CMSY7 1.0 %%CreationDate: 1991 Aug 15 07:21:52 % Copyright (C) 1997 American Mathematical Society. All Rights Reserved. 11 dict begin /FontInfo 7 dict dup begin /version (1.0) readonly def /Notice (Copyright (C) 1997 American Mathematical Society. All Rights Reserved) readonly def /FullName (CMSY7) readonly def /FamilyName (Computer Modern) readonly def /Weight (Medium) readonly def /ItalicAngle -14.035 def /isFixedPitch false def end readonly def /FontName /CMSY7 def /PaintType 0 def /FontType 1 def /FontMatrix [0.001 0 0 0.001 0 0] readonly def /Encoding 256 array 0 1 255 {1 index exch /.notdef put} for dup 0 /minus put dup 2 /multiply put dup 3 /asteriskmath put dup 21 /greaterequal put dup 48 /prime put dup 49 /infinity put dup 54 /negationslash put dup 109 /arrowdblbothv put dup 110 /backslash put readonly def /FontBBox{-15 -951 1252 782}readonly def currentdict end currentfile eexec D9D66F633B846A97B686A97E45A3D0AA052F09F9C8ADE9D907C058B87E9B6964 7D53359E51216774A4EAA1E2B58EC3176BD1184A633B951372B4198D4E8C5EF4 A213ACB58AA0A658908035BF2ED8531779838A960DFE2B27EA49C37156989C85 E21B3ABF72E39A89232CD9F4237FC80C9E64E8425AA3BEF7DED60B122A52922A 221A37D9A807DD01161779DDE7D251491EBF65A98C9FE2B1CF8D725A70281949 8F4AFFE638BBA6B12386C7F32BA350D62EA218D5B24EE612C2C20F43CD3BFD0D F02B185B692D7B27BEC7290EEFDCF92F95DDEB507068DE0B0B0351E3ECB8E443 E611BE0A41A1F8C89C3BC16B352C3443AB6F665EAC5E0CC4229DECFC58E15765 424C919C273E7FA240BE7B2E951AB789D127625BBCB7033E005050EB2E12B1C8 E5F3AD1F44A71957AD2CC53D917BFD09235601155886EE36D0C3DD6E7AA2EF9C C402C77FF1549E609A711FC3C211E64E8F263D60A57E9F2B47E3480B978AAF63 868AEA25DA3D5413467B76D2F02F8097D2841D1C12E89F6C6C51E20500301EC1 CE3EAF4742C13810DB4E900A472F42D4833A926A72718746BB66D1CDB563DC82 C497DC58BE3042E76D307F44BCF76BA97C39CD25AB078A2E5876BFB8AEB4DA47 6D28D500D3EC3F369C7AA1669A1BC08FF4B982B6B5C75AFF1DA4A4933E3A9E85 0F90D82006387F65DC8A32B5BD01F82F12EA62766DFCD35803D713C32992EFC7 16B5F6E2B8AD83B8E88CB015D7F97FB3F4FD934E75182644752F7E9439BB36AF 1939F8A5495AEE8AF44ED3EAFF2CB6D502EFA51C5CB9BD52A97329A8199553FB F08948981B5E9F89D28773CCE0F620CDFAAA810838E1540A9769368BA4A1A538 3DDD8D441EF7682E0780070F5595A8727C4D8F4B9C1287ABC86486F8D29BA30C 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cleartomark %%EndFont %%BeginFont: CMMI7 %!PS-AdobeFont-1.1: CMMI7 1.100 %%CreationDate: 1996 Jul 23 07:53:53 % Copyright (C) 1997 American Mathematical Society. All Rights Reserved. 11 dict begin /FontInfo 7 dict dup begin /version (1.100) readonly def /Notice (Copyright (C) 1997 American Mathematical Society. All Rights Reserved) readonly def /FullName (CMMI7) readonly def /FamilyName (Computer Modern) readonly def /Weight (Medium) readonly def /ItalicAngle -14.04 def /isFixedPitch false def end readonly def /FontName /CMMI7 def /PaintType 0 def /FontType 1 def /FontMatrix [0.001 0 0 0.001 0 0] readonly def /Encoding 256 array 0 1 255 {1 index exch /.notdef put} for dup 11 /alpha put dup 27 /sigma put dup 33 /omega put dup 58 /period put dup 59 /comma put dup 60 /less put dup 61 /slash put dup 62 /greater put dup 64 /partialdiff put dup 65 /A put dup 66 /B put dup 69 /E put dup 70 /F put dup 72 /H put dup 73 /I put dup 77 /M put dup 80 /P put dup 81 /Q put dup 82 /R put dup 83 /S put dup 84 /T put dup 86 /V put dup 88 /X put dup 97 /a put dup 98 /b put dup 99 /c put dup 100 /d put dup 104 /h put dup 105 /i put dup 106 /j put dup 107 /k put dup 109 /m put dup 110 /n put dup 112 /p put dup 115 /s put dup 116 /t put dup 120 /x put dup 121 /y put readonly def /FontBBox{0 -250 1171 750}readonly 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0000000000000000000000000000000000000000000000000000000000000000 0000000000000000000000000000000000000000000000000000000000000000 0000000000000000000000000000000000000000000000000000000000000000 0000000000000000000000000000000000000000000000000000000000000000 0000000000000000000000000000000000000000000000000000000000000000 0000000000000000000000000000000000000000000000000000000000000000 0000000000000000000000000000000000000000000000000000000000000000 cleartomark %%EndFont %%BeginFont: CMMI10 %!PS-AdobeFont-1.1: CMMI10 1.100 %%CreationDate: 1996 Jul 23 07:53:57 % Copyright (C) 1997 American Mathematical Society. All Rights Reserved. 11 dict begin /FontInfo 7 dict dup begin /version (1.100) readonly def /Notice (Copyright (C) 1997 American Mathematical Society. All Rights Reserved) readonly def /FullName (CMMI10) readonly def /FamilyName (Computer Modern) readonly def /Weight (Medium) readonly def /ItalicAngle -14.04 def /isFixedPitch false def end readonly def /FontName /CMMI10 def /PaintType 0 def /FontType 1 def /FontMatrix [0.001 0 0 0.001 0 0] readonly def /Encoding 256 array 0 1 255 {1 index exch /.notdef put} for dup 11 /alpha put dup 12 /beta put dup 13 /gamma put dup 14 /delta put dup 15 /epsilon1 put dup 17 /eta put dup 18 /theta put dup 20 /kappa put dup 21 /lambda put dup 24 /xi put dup 25 /pi put dup 26 /rho put dup 27 /sigma put dup 28 /tau put dup 33 /omega put dup 34 /epsilon put dup 58 /period put dup 59 /comma put dup 60 /less put dup 61 /slash put dup 62 /greater put dup 64 /partialdiff put dup 65 /A put dup 66 /B put dup 67 /C put dup 68 /D put dup 69 /E put dup 71 /G put dup 72 /H put dup 73 /I put dup 74 /J put dup 75 /K put dup 76 /L put dup 77 /M put dup 78 /N put dup 79 /O put dup 80 /P put dup 81 /Q put dup 82 /R put dup 83 /S put dup 84 /T put dup 85 /U put dup 86 /V put dup 88 /X put dup 89 /Y put dup 90 /Z put dup 96 /lscript put dup 97 /a put dup 98 /b put dup 99 /c put dup 100 /d put dup 101 /e put dup 102 /f put dup 103 /g put dup 104 /h put dup 105 /i put dup 106 /j put dup 107 /k put dup 108 /l put dup 109 /m put dup 110 /n put dup 111 /o put dup 112 /p put dup 113 /q put dup 114 /r put dup 115 /s put dup 116 /t put dup 117 /u put dup 118 /v put dup 119 /w put dup 120 /x put dup 121 /y put dup 122 /z put readonly def /FontBBox{-32 -250 1048 750}readonly def currentdict end currentfile eexec D9D66F633B846A97B686A97E45A3D0AA0529731C99A784CCBE85B4993B2EEBDE 3B12D472B7CF54651EF21185116A69AB1096ED4BAD2F646635E019B6417CC77B 532F85D811C70D1429A19A5307EF63EB5C5E02C89FC6C20F6D9D89E7D91FE470 B72BEFDA23F5DF76BE05AF4CE93137A219ED8A04A9D7D6FDF37E6B7FCDE0D90B 986423E5960A5D9FBB4C956556E8DF90CBFAEC476FA36FD9A5C8175C9AF513FE D919C2DDD26BDC0D99398B9F4D03D5993DFC0930297866E1CD0A319B6B1FD958 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b(.)41 b(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.) g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)87 b(35)606 4986 y(3.1.2)98 b(Left)20 b(and)f(right)h(preconditioning)51 b(.)42 b(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.) h(.)f(.)g(.)h(.)f(.)g(.)g(.)87 b(36)415 5088 y(3.2)f(Jacobi)20 b(Preconditioning)59 b(.)41 b(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g (.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.) f(.)g(.)g(.)87 b(37)606 5189 y(3.2.1)98 b(Block)20 b(Jacobi)g(Methods) 65 b(.)41 b(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g (.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)87 b(37)606 5291 y(3.2.2)98 b(Discussion)71 b(.)41 b(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.) f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g (.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)87 b(37)415 5393 y(3.3)f(SSOR)21 b(preconditioning)68 b(.)41 b(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g (.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.) f(.)g(.)g(.)87 b(37)415 5495 y(3.4)f(Incomplete)18 b(F)o(actorization)h (Preconditioners)73 b(.)41 b(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.) f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)87 b(38)606 5596 y(3.4.1)98 b(Creating)19 b(an)i(incomplete)d(f)o(actorization)29 b(.)41 b(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.) h(.)f(.)g(.)g(.)87 b(38)1878 5806 y(vii)p eop end %%Page: 8 8 TeXDict begin 8 7 bop 739 282 a FG(viii)2718 b Fu(CONTENTS)1054 515 y FG(3.4.2)98 b(Point)20 b(incomplete)f(f)o(actorizations)h(.)41 b(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g (.)h(.)f(.)g(.)g(.)h(.)87 b(39)1054 615 y(3.4.3)98 b(Block)20 b(f)o(actorization)f(methods)54 b(.)42 b(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.) h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)87 b(44)1054 715 y(3.4.4)98 b(Blocking)19 b(o)o(v)o(er)g(systems)i(of)f (partial)g(dif)n(ferential)e(equations)63 b(.)41 b(.)h(.)f(.)g(.)g(.)h (.)f(.)g(.)g(.)h(.)87 b(46)1054 814 y(3.4.5)98 b(Incomplete)18 b(LQ)j(f)o(actorizations)80 b(.)41 b(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.) g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)87 b(46)863 914 y(3.5)f(Polynomial)19 b(preconditioners)27 b(.)41 b(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.) g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)87 b(46)863 1013 y(3.6)f(Other)20 b(preconditioners)34 b(.)41 b(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f (.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)87 b(47)1054 1113 y(3.6.1)98 b(Preconditioning)17 b(by)j(the)g(symmetric)f (part)30 b(.)41 b(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g (.)h(.)f(.)g(.)g(.)h(.)87 b(47)1054 1213 y(3.6.2)98 b(The)20 b(use)g(of)g(f)o(ast)h(solv)o(ers)63 b(.)42 b(.)f(.)g(.)h(.)f(.)g(.)g (.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.) g(.)g(.)h(.)87 b(47)1054 1312 y(3.6.3)98 b(Alternating)19 b(Direction)g(Implicit)h(methods)70 b(.)41 b(.)g(.)h(.)f(.)g(.)g(.)h(.) f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)87 b(48)739 1495 y Fv(4)82 b(Related)20 b(Issues)2552 b(51)863 1595 y FG(4.1)86 b(Comple)o(x)19 b(Systems)39 b(.)i(.)g(.)g(.)h(.)f(.)g(.)g (.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.) g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)87 b(51)863 1694 y(4.2)f(Stopping)19 b(Criteria)65 b(.)41 b(.)g(.)g(.)h(.)f(.)g(.)g(.)h (.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.) h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)87 b(51)1054 1794 y(4.2.1)98 b(More)20 b(Details)h(about)e(Stopping)f(Criteria)72 b(.)41 b(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.) g(.)g(.)h(.)87 b(52)1054 1893 y(4.2.2)98 b(When)20 b FC(r)1578 1863 y Fz(\()p FB(i)p Fz(\))1679 1893 y FG(or)g Fx(k)p FC(r)1850 1863 y Fz(\()p FB(i)p Fz(\))1930 1893 y Fx(k)g FG(is)h(not)f(readily)f(a)n(v)n(ailable)71 b(.)42 b(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)87 b(55)1054 1993 y(4.2.3)98 b(Estimating)20 b Fx(k)p FC(A)1805 1963 y FA(\000)p Fz(1)1894 1993 y Fx(k)69 b FG(.)41 b(.)g(.)h(.)f(.)g (.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.) g(.)g(.)h(.)f(.)g(.)g(.)h(.)87 b(55)1054 2093 y(4.2.4)98 b(Stopping)19 b(when)g(progress)g(is)i(no)f(longer)f(being)g(made)59 b(.)41 b(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)87 b(56)1054 2192 y(4.2.5)98 b(Accounting)18 b(for)i(\003oating)f(point)h (errors)58 b(.)42 b(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g (.)g(.)h(.)f(.)g(.)g(.)h(.)87 b(56)863 2292 y(4.3)f(Data)21 b(Structures)61 b(.)42 b(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.) f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g (.)h(.)f(.)g(.)g(.)h(.)87 b(56)1054 2392 y(4.3.1)98 b(Surv)o(e)o(y)19 b(of)g(Sparse)i(Matrix)e(Storage)h(F)o(ormats)53 b(.)41 b(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)87 b(57)1054 2491 y(4.3.2)98 b(Matrix)20 b(v)o(ector)f(products)47 b(.)42 b(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.) f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)87 b(60)1054 2591 y(4.3.3)98 b(Sparse)20 b(Incomplete)e(F)o(actorizations)76 b(.)41 b(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.) h(.)f(.)g(.)g(.)h(.)87 b(63)863 2690 y(4.4)f(P)o(arallelism)80 b(.)41 b(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.) g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f (.)g(.)g(.)h(.)87 b(67)1054 2790 y(4.4.1)98 b(Inner)19 b(products)76 b(.)42 b(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f (.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.) h(.)87 b(67)1054 2890 y(4.4.2)98 b(V)-9 b(ector)19 b(updates)68 b(.)42 b(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.) f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)87 b(69)1054 2989 y(4.4.3)98 b(Matrix-v)o(ector)18 b(products)40 b(.)i(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f (.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)87 b(69)1054 3089 y(4.4.4)98 b(Preconditioning)26 b(.)42 b(.)f(.)g(.)g(.)h(.)f(.)g (.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.) g(.)g(.)h(.)f(.)g(.)g(.)h(.)87 b(69)1054 3189 y(4.4.5)98 b(W)-7 b(a)n(v)o(efronts)20 b(in)g(the)g(Gauss-Seidel)g(and)g (Conjugate)e(Gradient)h(methods)81 b(.)41 b(.)g(.)g(.)h(.)87 b(70)1054 3288 y(4.4.6)98 b(Block)o(ed)20 b(operations)e(in)j(the)f (GMRES)h(method)65 b(.)42 b(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)h (.)f(.)g(.)g(.)h(.)87 b(71)739 3471 y Fv(5)82 b(Remaining)21 b(topics)2439 b(73)863 3571 y FG(5.1)86 b(The)20 b(Lanczos)g (Connection)56 b(.)41 b(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g (.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.) 87 b(73)863 3670 y(5.2)f(Block)20 b(and)g FC(s)p FG(-step)g(Iterati)n (v)o(e)f(Methods)33 b(.)41 b(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.) g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)87 b(74)863 3770 y(5.3)f(Reduced)20 b(System)g(Preconditioning)27 b(.)41 b(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.) g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)87 b(74)863 3869 y(5.4)f(Domain)20 b(Decomposition)e(Methods)29 b(.)41 b(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h (.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)87 b(75)1054 3969 y(5.4.1)98 b(Ov)o(erlapping)18 b(Subdomain)g(Methods)57 b(.)41 b(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.) h(.)f(.)g(.)g(.)h(.)87 b(76)1054 4069 y(5.4.2)98 b(Non-o)o(v)o (erlapping)16 b(Subdomain)i(Methods)31 b(.)41 b(.)g(.)g(.)h(.)f(.)g(.)g (.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)87 b(77)1054 4168 y(5.4.3)98 b(Further)19 b(Remarks)62 b(.)41 b(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g (.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)87 b(79)863 4268 y(5.5)f(Multigrid)19 b(Methods)71 b(.)41 b(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h (.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)87 b(80)863 4368 y(5.6)f(Ro)n(w)21 b(Projection)e(Methods)59 b(.)41 b(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.) g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)87 b(81)739 4550 y Fv(A)64 b(Obtaining)20 b(the)h(Softwar)o(e)2224 b(83)739 4733 y(B)69 b(Ov)o(er)o(view)20 b(of)g(the)g(BLAS)2258 b(85)739 4915 y(C)64 b(Glossary)2741 b(87)863 5015 y FG(C.1)73 b(Notation)36 b(.)42 b(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.) g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h (.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)87 b(91)739 5198 y Fv(D)64 b(Flo)o(wchart)20 b(of)g(iterati)o(v)o(e)f(methods)1925 b(107)p eop end %%Page: 9 9 TeXDict begin 9 8 bop 291 1179 a FF(List)52 b(of)f(Figur)l(es)415 1694 y FG(2.1)86 b(The)20 b(Jacobi)g(Method)59 b(.)41 b(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g (.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)129 b(8)415 1794 y(2.2)86 b(The)20 b(Gauss-Seidel)g(Method)f(.)42 b(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g (.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)129 b(9)415 1893 y(2.3)86 b(The)20 b(SOR)h(Method)47 b(.)42 b(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g (.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)87 b(10)415 1993 y(2.4)f(The)20 b(SSOR)h(Method)64 b(.)41 b(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g (.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)87 b(12)415 2093 y(2.5)f(The)20 b(Preconditioned)d(Conjugate)i(Gradient)g (Method)30 b(.)41 b(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g (.)h(.)f(.)g(.)g(.)87 b(13)415 2192 y(2.6)f(The)20 b(Preconditioned)d (GMRES)p Fy(\()p FC(m)p Fy(\))22 b FG(Method)71 b(.)41 b(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h (.)f(.)g(.)g(.)87 b(18)415 2292 y(2.7)f(The)20 b(Preconditioned)d (BiConjugate)i(Gradient)h(Method)75 b(.)41 b(.)h(.)f(.)g(.)g(.)h(.)f(.) g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)87 b(20)415 2392 y(2.8)f(The)20 b(Preconditioned)d(Quasi)k(Minimal)f(Residual)g(Method)f (without)g(Look-ahead)48 b(.)42 b(.)f(.)g(.)g(.)87 b(22)415 2491 y(2.9)f(The)20 b(Preconditioned)d(Conjugate)i(Gradient)g(Squared)g (Method)48 b(.)41 b(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.) 87 b(23)415 2591 y(2.10)44 b(The)20 b(Preconditioned)d(BiConjugate)i (Gradient)h(Stabilized)g(Method)33 b(.)42 b(.)f(.)g(.)g(.)h(.)f(.)g(.)h (.)f(.)g(.)g(.)87 b(24)415 2690 y(2.11)44 b(The)20 b(Preconditioned)d (Chebyshe)n(v)i(Method)66 b(.)41 b(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g (.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)87 b(26)415 2873 y(3.1)f(Preconditioner)18 b(solv)o(e)h(of)h(a)h(system)f FC(M)9 b(x)23 b Fy(=)g FC(y)s FG(,)d(with)h FC(M)31 b Fy(=)23 b FC(LU)90 b FG(.)41 b(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g (.)g(.)87 b(39)415 2973 y(3.2)f(Preconditioner)22 b(solv)o(e)i(of)h(a)g (system)g FC(M)9 b(x)31 b Fy(=)g FC(y)s FG(,)25 b(with)g FC(M)40 b Fy(=)31 b(\()p FC(D)24 b Fy(+)d FC(L)p Fy(\))p FC(D)2847 2943 y FA(\000)p Fz(1)2936 2973 y Fy(\()p FC(D)j Fy(+)e FC(U)9 b Fy(\))31 b(=)606 3072 y(\()p FC(D)21 b Fy(+)d FC(L)p Fy(\)\()p FC(I)25 b Fy(+)18 b FC(D)1147 3042 y FA(\000)p Fz(1)1237 3072 y FC(U)9 b Fy(\))p FG(.)76 b(.)41 b(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.) h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)87 b(39)415 3172 y(3.3)f(Construction)23 b(of)h(a)g FC(D)r FG(-)p FC(I)7 b(LU)33 b FG(incomplete)22 b(f)o(actorization)h (preconditioner)m(,)e(storing)i(the)h(in-)606 3272 y(v)o(erses)c(of)g (the)g(pi)n(v)n(ots)63 b(.)41 b(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h (.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.) g(.)h(.)f(.)g(.)g(.)87 b(40)415 3371 y(3.4)f(W)-7 b(a)n(v)o(efront)15 b(solution)g(of)h Fy(\()p FC(D)5 b Fy(+)s FC(L)p Fy(\))p FC(x)22 b Fy(=)h FC(u)16 b FG(from)f(a)h(central)g(dif)n(ference)d (problem)i(on)g(a)i(domain)606 3471 y(of)j FC(n)e Fx(\002)g FC(n)j FG(points.)40 b(.)h(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g (.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.) f(.)g(.)h(.)f(.)g(.)g(.)87 b(42)415 3571 y(3.5)f(Preconditioning)29 b(step)k(algorithm)e(for)g(a)i(Neumann)d(e)o(xpansion)h FC(M)2705 3540 y Fz(\()p FB(p)p Fz(\))2840 3571 y Fx(\031)45 b FC(M)3040 3540 y FA(\000)p Fz(1)3161 3571 y FG(of)32 b(an)606 3670 y(incomplete)19 b(f)o(actorization)f FC(M)32 b Fy(=)23 b(\()p FC(I)i Fy(+)18 b FC(L)p Fy(\))p FC(D)r Fy(\()p FC(I)26 b Fy(+)18 b FC(U)9 b Fy(\))p FG(.)36 b(.)41 b(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.) g(.)87 b(43)415 3770 y(3.6)f(Block)20 b(v)o(ersion)f(of)h(a)h FC(D)r FG(-)p FC(I)7 b(LU)28 b FG(f)o(actorization)51 b(.)41 b(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.) f(.)g(.)h(.)f(.)g(.)g(.)87 b(44)415 3869 y(3.7)f(Algorithm)19 b(for)g(approximating)e(the)k(in)m(v)o(erse)e(of)g(a)i(banded)e(matrix) 77 b(.)42 b(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)87 b(45)415 3969 y(3.8)f(Incomplete)18 b(block)i(f)o(actorization)e(of)i (a)h(block)e(tridiagonal)f(matrix)81 b(.)42 b(.)f(.)g(.)g(.)h(.)f(.)g (.)h(.)f(.)g(.)g(.)87 b(45)415 4152 y(4.1)f(Pro\002le)20 b(of)g(a)h(nonsymmetric)d(sk)o(yline)h(or)h(v)n(ariable-band)d(matrix.) 60 b(.)41 b(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h(.)f(.)g(.)g(.)87 b(61)415 4251 y(4.2)f(A)21 b(rearrangement)c(of)j(Conjugate)f(Gradient) g(for)g(parallelism)54 b(.)41 b(.)g(.)g(.)h(.)f(.)g(.)g(.)h(.)f(.)g(.)h (.)f(.)g(.)g(.)87 b(68)1890 5806 y(ix)p eop end %%Page: 10 10 TeXDict begin 10 9 bop 739 282 a FG(x)2552 b Fu(LIST)20 b(OF)h(FIGURES)p eop end %%Page: 1 11 TeXDict begin 1 10 bop 291 1139 a FD(Chapter)44 b(1)291 1556 y FF(Intr)l(oduction)291 1989 y FG(Which)20 b(of)g(the)g(follo)n (wing)e(statements)j(is)g(true?)415 2159 y Fx(\017)41 b FG(Users)31 b(w)o(ant)f(\223black)f(box\224)g(softw)o(are)h(that)g (the)o(y)f(can)h(use)g(with)g(complete)f(con\002dence)g(for)g(general) 498 2258 y(problem)19 b(classes)i(without)e(ha)n(ving)g(to)i (understand)d(the)i(\002ne)g(algorithmic)f(details.)415 2430 y Fx(\017)41 b FG(Users)20 b(w)o(ant)g(to)g(be)g(able)f(to)h(tune) f(data)h(structures)f(for)g(a)h(particular)e(application,)g(e)n(v)o(en) h(if)h(the)f(softw)o(are)498 2529 y(is)i(not)f(as)h(reliable)f(as)h (that)f(pro)o(vided)e(for)h(general)g(methods.)291 2699 y(It)h(turns)g(out)g(both)f(are)h(true,)g(for)f(dif)n(ferent)g(groups)g (of)h(users.)415 2800 y(T)m(raditionally)-5 b(,)23 b(users)i(ha)n(v)o (e)f(ask)o(ed)h(for)f(and)g(been)f(pro)o(vided)g(with)h(black)g(box)g (softw)o(are)g(in)h(the)g(form)e(of)291 2900 y(mathematical)30 b(libraries)g(such)h(as)h FE(LAPACK)p FG(,)f FE(LINPACK)p FG(,)f FE(NAG)p FG(,)h(and)f FE(IMSL)p FG(.)h(More)g(recently)-5 b(,)32 b(the)f(high-)291 2999 y(performance)23 b(community)i(has)i (disco)o(v)o(ered)d(that)j(the)o(y)f(must)h(write)g(custom)f(softw)o (are)g(for)g(their)h(problem.)291 3099 y(Their)g(reasons)g(include)f (inadequate)g(functionality)f(of)j(e)o(xisting)f(softw)o(are)g (libraries,)h(data)g(structures)f(that)291 3199 y(are)d(not)g(natural)g (or)h(con)m(v)o(enient)d(for)i(a)h(particular)e(problem,)h(and)g(o)o(v) o(erly)f(general)g(softw)o(are)i(that)f(sacri\002ces)291 3298 y(too)19 b(much)h(performance)d(when)j(applied)f(to)h(a)h(special) f(case)h(of)e(interest.)415 3399 y(Can)h(we)g(meet)g(the)g(needs)f(of)h (both)f(groups)f(of)i(users?)25 b(W)-7 b(e)21 b(belie)n(v)o(e)e(we)h (can.)k(Accordingly)-5 b(,)17 b(in)j(this)h(book,)291 3499 y(we)c(introduce)f(the)i(use)f(of)h Ft(templates)p FG(.)23 b(A)18 b(template)f(is)i(a)f(description)e(of)h(a)h(general)e (algorithm)g(rather)h(than)g(the)291 3598 y(e)o(x)o(ecutable)d(object)i (code)g(or)g(the)h(source)f(code)g(more)f(commonly)g(found)f(in)j(a)g (con)m(v)o(entional)d(softw)o(are)i(library)-5 b(.)291 3698 y(Ne)n(v)o(ertheless,)26 b(although)e(templates)i(are)g(general)f (descriptions)g(of)h(k)o(e)o(y)f(algorithms,)h(the)o(y)g(of)n(fer)e (whate)n(v)o(er)291 3798 y(de)o(gree)c(of)i(customization)f(the)h(user) g(may)f(desire.)31 b(F)o(or)21 b(e)o(xample,)g(the)o(y)h(can)f(be)h (con\002gured)e(for)i(the)g(speci\002c)291 3897 y(data)e(structure)f (of)h(a)g(problem)f(or)h(for)f(the)i(speci\002c)f(computing)e(system)i (on)g(which)g(the)g(problem)e(is)j(to)g(run.)415 3998 y(W)-7 b(e)21 b(focus)f(on)g(the)g(use)g(of)g(iterati)n(v)o(e)g (methods)f(for)h(solving)f(lar)o(ge)g(sparse)h(systems)h(of)f(linear)g (equations.)415 4099 y(Man)o(y)i(methods)f(e)o(xist)i(for)f(solving)g (such)g(problems.)31 b(The)22 b(trick)h(is)g(to)g(\002nd)g(the)f(most)h (ef)n(fecti)n(v)o(e)e(method)291 4199 y(for)j(the)h(problem)e(at)i (hand.)39 b(Unfortunately)-5 b(,)22 b(a)k(method)d(that)i(w)o(orks)g (well)g(for)g(one)f(problem)f(type)i(may)f(not)291 4298 y(w)o(ork)19 b(as)i(well)g(for)e(another)-5 b(.)24 b(Indeed,)19 b(it)i(may)e(not)h(w)o(ork)g(at)g(all.)415 4399 y(Thus,)37 b(besides)e(pro)o(viding)c(templates,)38 b(we)c(suggest)g(ho)n(w)g(to)h (choose)e(and)h(implement)f(an)h(ef)n(fecti)n(v)o(e)291 4499 y(method,)29 b(and)f(ho)n(w)h(to)g(specialize)f(a)i(method)d(to)i (speci\002c)g(matrix)f(types.)51 b(W)-7 b(e)30 b(restrict)f(ourselv)o (es)f(to)h Ft(iter)n(-)291 4599 y(ative)e(methods)p FG(,)h(which)f(w)o (ork)g(by)g(repeatedly)f(impro)o(ving)f(an)i(approximate)e(solution)i (until)g(it)h(is)h(accurate)291 4698 y(enough.)36 b(These)24 b(methods)g(access)h(the)g(coef)n(\002cient)e(matrix)h FC(A)i FG(of)e(the)h(linear)f(system)h(only)f(via)g(the)h(matrix-)291 4798 y(v)o(ector)c(product)f FC(y)30 b Fy(=)d FC(A)20 b Fx(\001)g FC(x)k FG(\(and)d(perhaps)g FC(z)31 b Fy(=)c FC(A)1830 4768 y FB(T)1902 4798 y Fx(\001)20 b FC(x)p FG(\).)33 b(Thus)22 b(the)g(user)g(need)g(only)g(supply)f(a)i (subroutine)291 4898 y(for)h(computing)f FC(y)28 b FG(\(and)c(perhaps)g FC(z)t FG(\))g(gi)n(v)o(en)g FC(x)p FG(,)j(which)e(permits)f(full)h(e)o (xploitation)e(of)i(the)g(sparsity)g(or)g(other)291 4997 y(special)20 b(structure)f(of)h FC(A)p FG(.)415 5098 y(W)-7 b(e)21 b(belie)n(v)o(e)d(that)i(after)f(reading)e(this)j(book,)e (applications)g(de)n(v)o(elopers)g(will)i(be)f(able)g(to)h(use)g (templates)f(to)291 5198 y(get)j(their)f(program)f(running)g(on)h(a)i (parallel)e(machine)g(quickly)-5 b(.)28 b(Nonspecialists)22 b(will)g(kno)n(w)f(ho)n(w)h(to)g(choose)291 5297 y(and)28 b(implement)h(an)g(approach)e(to)j(solv)o(e)f(a)h(particular)e (problem.)51 b(Specialists)30 b(will)h(be)e(able)g(to)h(assemble)291 5397 y(and)c(modify)g(their)g(codes\227without)g(ha)n(ving)g(to)h(mak)o (e)g(the)g(huge)f(in)m(v)o(estment)f(that)i(has,)i(up)e(to)g(no)n(w)-5 b(,)28 b(been)291 5497 y(required)15 b(to)j(tune)g(lar)o(ge-scale)e (applications)h(for)g(each)g(particular)f(machine.)23 b(Finally)-5 b(,)18 b(we)g(hope)f(that)g(all)i(users)291 5596 y(will)j(gain)e(a)h(better)g(understanding)d(of)j(the)h (algorithms)d(emplo)o(yed.)27 b(While)21 b(education)f(has)h(not)g (been)g(one)f(of)1901 5806 y(1)p eop end %%Page: 2 12 TeXDict begin 2 11 bop 739 282 a FG(2)2089 b Fu(CHAPTER)21 b(1.)46 b(INTR)m(ODUCTION)739 515 y FG(the)21 b(traditional)f(goals)i (of)f(mathematical)f(softw)o(are,)h(we)h(belie)n(v)o(e)e(that)i(our)e (approach)f(will)j(go)f(a)h(long)f(w)o(ay)g(in)739 615 y(pro)o(viding)c(such)j(a)h(v)n(aluable)e(service.)739 896 y Fs(1.1)119 b(Wh)n(y)30 b(Use)g(T)-11 b(emplates?)739 1082 y FG(T)-6 b(emplates)21 b(of)n(fer)f(three)h(signi\002cant)h(adv)n (antages.)27 b(First,)22 b(templates)g(are)f(general)g(and)g(reusable.) 28 b(Thus,)21 b(the)o(y)739 1182 y(can)28 b(simplify)g(ports)g(to)g(di) n(v)o(erse)f(machines.)49 b(This)28 b(feature)f(is)j(important)c(gi)n (v)o(en)h(the)i(di)n(v)o(ersity)e(of)h(parallel)739 1281 y(architectures.)863 1381 y(Second,)f(templates)f(e)o(xploit)f(the)h(e) o(xpertise)f(of)h(tw)o(o)g(distinct)h(groups.)41 b(The)26 b(e)o(xpert)f(numerical)f(analyst)739 1481 y(creates)i(a)h(template)f (re\003ecting)f(in-depth)g(kno)n(wledge)f(of)i(a)g(speci\002c)h (numerical)e(technique.)41 b(The)26 b(compu-)739 1580 y(tational)f(scientist)h(then)e(pro)o(vides)g(\223v)n(alue-added\224)e (capability)i(to)i(the)f(general)f(template)h(description,)f(cus-)739 1680 y(tomizing)19 b(it)i(for)e(speci\002c)i(conte)o(xts)e(or)h (applications)f(needs.)863 1780 y(And)30 b(third,)j(templates)d(are)g (not)g(language)f(speci\002c.)56 b(Rather)m(,)33 b(the)o(y)c(are)i (displayed)e(in)i(an)f(Algol-lik)o(e)739 1879 y(structure,)f(which)f (is)h(readily)e(translatable)h(into)f(the)i(tar)o(get)e(language)f (such)i(as)h FE(FORTRAN)f FG(\(with)g(the)g(use)739 1979 y(of)g(the)h(Basic)h(Linear)e(Algebra)g(Subprograms,)g(or)h FE(BLAS)p FG(,)f(whene)n(v)o(er)f(possible\))h(and)g FE(C)p FG(.)h(By)h(using)e(these)739 2079 y(f)o(amiliar)21 b(styles,)i(we)f(belie)n(v)o(e)f(that)h(the)g(users)g(will)g(ha)n(v)o (e)g(trust)g(in)g(the)g(algorithms.)28 b(W)-7 b(e)23 b(also)f(hope)f(that)h(users)739 2178 y(will)f(gain)e(a)i(better)f (understanding)d(of)j(numerical)e(techniques)h(and)h(parallel)g (programming.)863 2278 y(F)o(or)g(each)g(template,)g(we)g(pro)o(vide)e (some)i(or)g(all)h(of)f(the)g(follo)n(wing:)863 2462 y Fx(\017)41 b FG(a)21 b(mathematical)e(description)g(of)h(the)g(\003o) n(w)g(of)g(the)g(iteration;)863 2628 y Fx(\017)41 b FG(discussion)20 b(of)g(con)m(v)o(er)o(gence)c(and)k(stopping)f(criteria;)863 2795 y Fx(\017)41 b FG(suggestions)20 b(for)f(applying)g(a)h(method)f (to)h(special)h(matrix)e(types)h(\()p Ft(e)o(.g)o(.)p FG(,)f(banded)f(systems\);)863 2962 y Fx(\017)41 b FG(advice)20 b(for)f(tuning)g(\(for)h(e)o(xample,)e(which)i(preconditioners)d(are)j (applicable)f(and)h(which)f(are)i(not\);)863 3129 y Fx(\017)41 b FG(tips)21 b(on)f(parallel)g(implementations;)e(and)863 3295 y Fx(\017)41 b FG(hints)21 b(as)g(to)f(when)g(to)g(use)g(a)h (method,)d(and)i(why)-5 b(.)863 3479 y(F)o(or)20 b(each)g(of)g(the)g 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Fy(=)23 b(1)p FC(;)14 b Fy(2)p FC(;)g(:)g(:)g(:)e(;)i(i)k Fx(\000)g Fy(1)1599 1132 y FC(\033)27 b Fy(=)22 b FC(\033)g Fy(+)c FC(a)1956 1144 y FB(i;j)2034 1132 y FC(x)2081 1089 y Fz(\()p FB(k)q Fz(\))2081 1155 y FB(j)1454 1237 y Fv(end)1454 1336 y(f)n(or)40 b FC(j)28 b Fy(=)23 b FC(i)18 b Fy(+)g(1)p FC(;)c(:)g(:)g(:)f(;)h(n)1599 1453 y(\033)27 b Fy(=)22 b FC(\033)g Fy(+)c FC(a)1956 1465 y FB(i;j)2034 1453 y FC(x)2081 1410 y Fz(\()p FB(k)q FA(\000)p Fz(1\))2081 1476 y FB(j)1454 1557 y Fv(end)1454 1674 y FC(x)1501 1630 y Fz(\()p FB(k)q Fz(\))1501 1697 y FB(i)1617 1674 y Fy(=)23 b(\()p FC(b)1773 1686 y FB(i)1819 1674 y Fx(\000)18 b FC(\033)s Fy(\))p FC(=a)2070 1686 y FB(i;i)1308 1773 y Fv(end)1308 1873 y FG(check)i(con)m(v)o(er)o (gence;)c(continue)j(if)h(necessary)1163 1972 y Fv(end)p 3119 2110 V 722 2113 2400 4 v 1293 2268 a FG(Figure)g(2.2:)25 b(The)19 b(Gauss-Seidel)h(Method)291 2551 y(results)g(are)g(used)g(as)h (soon)f(as)h(the)o(y)e(are)h(a)n(v)n(ailable,)g(we)g(obtain)g(the)g 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Fy(\))1043 4704 y FA(\000)p Fz(1)1132 4739 y Fy(\()p FC(U)9 b(x)1277 4704 y Fz(\()p FB(k)q FA(\000)p Fz(1\))1473 4739 y Fy(+)18 b FC(b)p Fy(\))p FC(:)1747 b FG(\(2.6\))291 4904 y(As)17 b(before,)e FC(D)r FG(,)i Fx(\000)p FC(L)f FG(and)g Fx(\000)p FC(U)25 b FG(represent)15 b(the)h(diagonal,)f(lo)n(wer)n(-triangular)m(,)f(and)i (upper)n(-triangular)c(parts)k(of)g FC(A)p FG(,)291 5004 y(respecti)n(v)o(ely)-5 b(.)415 5103 y(The)20 b(pseudocode)e(for)h(the) h(Gauss-Seidel)g(algorithm)f(is)i(gi)n(v)o(en)e(in)h(Figure)g(2.2.)291 5341 y Fp(2.2.3)98 b(The)26 b(Successi)o(v)o(e)g(Ov)o(err)n(elaxation)f (Method)291 5497 y FG(The)16 b(Successi)n(v)o(e)h(Ov)o(errelaxation)e (Method,)h(or)h(SOR,)h(is)g(de)n(vised)e(by)h(applying)f(e)o (xtrapolation)e(to)k(the)f(Gauss-)291 5596 y(Seidel)e(method.)22 b(This)16 b(e)o(xtrapolation)d(tak)o(es)j(the)f(form)g(of)g(a)h (weighted)e(a)n(v)o(erage)h(between)f(the)i(pre)n(vious)e(iterate)p eop end %%Page: 10 20 TeXDict begin 10 19 bop 739 282 a FG(10)1825 b Fu(CHAPTER)21 b(2.)45 b(ITERA)-9 b(TIVE)19 b(METHODS)p 1170 436 2400 4 v 1170 2210 4 1775 v 1611 617 a FG(Choose)h(an)g(initial)h(guess)f FC(x)2447 587 y Fz(\(0\))2557 617 y FG(to)h(the)f(solution)f FC(x)p FG(.)1611 717 y Fv(f)n(or)41 b FC(k)26 b Fy(=)c(1)p FC(;)14 b Fy(2)p FC(;)g(:)g(:)g(:)1757 816 y Fv(f)n(or)40 b FC(i)23 b Fy(=)g(1)p FC(;)14 b Fy(2)p FC(;)g(:)g(:)g(:)e(;)i(n)1902 916 y(\033)27 b Fy(=)22 b(0)1902 1016 y Fv(f)n(or)41 b FC(j)28 b Fy(=)22 b(1)p FC(;)14 b Fy(2)p FC(;)g(:)g(:)g(:)f(;)h(i)k Fx(\000)g Fy(1)2048 1132 y FC(\033)26 b Fy(=)d FC(\033)f Fy(+)c FC(a)2405 1144 y FB(i;j)2483 1132 y FC(x)2530 1089 y Fz(\()p FB(k)q Fz(\))2530 1155 y FB(j)1902 1237 y Fv(end)1902 1336 y(f)n(or)41 b FC(j)28 b Fy(=)22 b FC(i)c Fy(+)g(1)p FC(;)c(:)g(:)g(:)f(;)h(n)2048 1453 y(\033)26 b Fy(=)d FC(\033)f Fy(+)c FC(a)2405 1465 y FB(i;j)2483 1453 y FC(x)2530 1410 y Fz(\()p FB(k)q FA(\000)p Fz(1\))2530 1476 y FB(j)1902 1557 y Fv(end)1902 1657 y FC(\033)27 b Fy(=)22 b(\()p FC(b)2131 1669 y FB(i)2177 1657 y Fx(\000)c FC(\033)s Fy(\))p FC(=a)2428 1669 y FB(i;i)1902 1773 y FC(x)1949 1730 y Fz(\()p FB(k)q Fz(\))1949 1796 y FB(i)2065 1773 y Fy(=)23 b FC(x)2200 1730 y Fz(\()p FB(k)q FA(\000)p Fz(1\))2200 1796 y FB(i)2397 1773 y Fy(+)18 b FC(!)s Fy(\()p FC(\033)k Fx(\000)c FC(x)2766 1730 y Fz(\()p FB(k)q FA(\000)p Fz(1\))2766 1796 y FB(i)2944 1773 y Fy(\))1757 1873 y Fv(end)1757 1972 y FG(check)h(con)m(v)o(er)o (gence;)d(continue)j(if)i(necessary)1611 2072 y Fv(end)p 3567 2210 V 1170 2213 2400 4 v 1880 2368 a FG(Figure)f(2.3:)k(The)c (SOR)h(Method)739 2658 y(and)f(the)g(computed)e(Gauss-Seidel)i(iterate) g(successi)n(v)o(ely)f(for)h(each)g(component:)946 2852 y FC(x)993 2809 y Fz(\()p FB(k)q Fz(\))993 2875 y FB(i)1110 2852 y Fy(=)i FC(!)8 b Fy(\026)-47 b FC(x)1299 2809 y Fz(\()p FB(k)q Fz(\))1299 2875 y FB(i)1411 2852 y Fy(+)18 b(\(1)g Fx(\000)g FC(!)s Fy(\))p FC(x)1803 2809 y Fz(\()p FB(k)q FA(\000)p Fz(1\))1803 2875 y FB(i)739 3029 y FG(\(where)25 b Fy(\026)-48 b FC(x)22 b FG(denotes)e(a)h(Gauss-Seidel)f(iterate,)g (and)g FC(!)k FG(is)d(the)g(e)o(xtrapolation)d(f)o(actor\).)25 b(The)20 b(idea)g(is)i(to)e(choose)g(a)739 3128 y(v)n(alue)f(for)h FC(!)j FG(that)e(will)g(accelerate)e(the)h(rate)h(of)f(con)m(v)o(er)o (gence)c(of)k(the)g(iterates)g(to)h(the)f(solution.)863 3232 y(In)g(matrix)g(terms,)g(the)g(SOR)h(algorithm)e(can)h(be)g (written)g(as)h(follo)n(ws:)946 3412 y FC(x)993 3378 y Fz(\()p FB(k)q Fz(\))1110 3412 y Fy(=)h(\()p FC(D)f Fx(\000)d FC(!)s(L)p Fy(\))1546 3378 y FA(\000)p Fz(1)1635 3412 y Fy(\()p FC(!)s(U)27 b Fy(+)18 b(\(1)g Fx(\000)g FC(!)s Fy(\))p FC(D)r Fy(\))p FC(x)2301 3378 y Fz(\()p FB(k)q FA(\000)p Fz(1\))2498 3412 y Fy(+)g FC(!)s Fy(\()p FC(D)i Fx(\000)e FC(!)s(L)p Fy(\))2984 3378 y FA(\000)p Fz(1)3073 3412 y FC(b:)711 b FG(\(2.7\))863 3589 y(The)20 b(pseudocode)e(for)i(the)g(SOR)h(algorithm)e(is)i(gi)n(v)o(en)e(in)h (Figure)g(2.3.)739 3829 y Fv(Choosing)g(the)g(V)-8 b(alue)21 b(of)f FC(!)739 3992 y FG(If)i FC(!)29 b Fy(=)e(1)p FG(,)22 b(the)g(SOR)i(method)c(simpli\002es)j(to)f(the)h(Gauss-Seidel)e (method.)30 b(A)23 b(theorem)d(due)i(to)g(Kahan)g([129)n(])739 4091 y(sho)n(ws)j(that)h(SOR)g(f)o(ails)g(to)g(con)m(v)o(er)o(ge)c(if)k FC(!)j FG(is)d(outside)f(the)g(interv)n(al)g Fy(\(0)p FC(;)14 b Fy(2\))p FG(.)40 b(Though)24 b(technically)g(the)h(term)739 4191 y Ft(underr)m(elaxation)19 b FG(should)i(be)h(used)g(when)g Fy(0)k FC(<)g(!)j(<)d Fy(1)p FG(,)c(for)f(con)m(v)o(enience)e(the)j (term)g(o)o(v)o(errelaxation)d(is)k(no)n(w)739 4290 y(used)d(for)f(an)o (y)h(v)n(alue)f(of)h FC(!)26 b Fx(2)d Fy(\(0)p FC(;)14 b Fy(2\))p FG(.)863 4394 y(In)23 b(general,)f(it)h(is)h(not)e(possible) h(to)g(compute)e(in)i(adv)n(ance)e(the)i(v)n(alue)f(of)g FC(!)k FG(that)d(is)h(optimal)e(with)h(respect)739 4493 y(to)18 b(the)h(rate)f(of)g(con)m(v)o(er)o(gence)c(of)k(SOR.)h(Ev)o(en) e(when)h(it)h(is)g(possible)f(to)h(compute)e(the)h(optimal)f(v)n(alue)h (for)g FC(!)s FG(,)g(the)739 4593 y(e)o(xpense)25 b(of)h(such)g 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b(METHODS)p 1020 436 2700 4 v 1020 3022 4 2587 v 1464 617 a FG(Compute)g FC(r)1828 587 y Fz(\(0\))1941 617 y Fy(=)k FC(b)18 b Fx(\000)g FC(Ax)2275 587 y Fz(\(0\))2386 617 y FG(for)h(some)h(initial)h(guess)f FC(x)3166 587 y Fz(\(0\))3256 617 y FG(.)1464 721 y(Choose)k Fy(~)-46 b FC(r)1773 691 y Fz(\(0\))1884 721 y FG(\(for)19 b(e)o(xample,)j Fy(~)-46 b FC(r)2389 691 y Fz(\(0\))2502 721 y Fy(=)23 b FC(r)2629 691 y Fz(\(0\))2719 721 y FG(\).)1464 820 y Fv(f)n(or)41 b FC(i)22 b Fy(=)h(1)p FC(;)14 b Fy(2)p FC(;)g(:)g(:)g(:)1610 924 y FG(solv)o(e)19 b FC(M)9 b(z)1937 894 y Fz(\()p FB(i)p FA(\000)p Fz(1\))2124 924 y Fy(=)22 b FC(r)2250 894 y Fz(\()p FB(i)p FA(\000)p Fz(1\))1610 1028 y FG(solv)o(e)d FC(M)1894 998 y FB(T)1951 1028 y Fy(~)-47 b FC(z)1989 998 y Fz(\()p FB(i)p FA(\000)p Fz(1\))2176 1028 y Fy(=)27 b(~)-46 b FC(r)2303 998 y Fz(\()p FB(i)p FA(\000)p Fz(1\))1610 1141 y FC(\032)1653 1153 y FB(i)p FA(\000)p Fz(1)1788 1141 y Fy(=)23 b FC(z)1919 1111 y Fz(\()p FB(i)p FA(\000)p Fz(1\))2079 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Fy(=)27 b(~)-47 b FC(z)2071 1924 y Fz(\()p FB(i)p FA(\000)p Fz(1\))2254 1954 y Fy(+)18 b FC(\014)2384 1966 y FB(i)p FA(\000)p Fz(1)2503 1954 y Fy(~)-49 b FC(p)2538 1924 y Fz(\()p FB(i)p FA(\000)p Fz(1\))1610 2054 y Fv(endif)1610 2157 y FC(q)1650 2127 y Fz(\()p FB(i)p Fz(\))1752 2157 y Fy(=)23 b FC(Ap)1944 2127 y Fz(\()p FB(i)p Fz(\))1616 2261 y Fy(~)-48 b FC(q)1650 2231 y Fz(\()p FB(i)p Fz(\))1752 2261 y Fy(=)23 b FC(A)1902 2231 y FB(T)1962 2261 y Fy(~)-50 b FC(p)1996 2231 y Fz(\()p FB(i)p Fz(\))1610 2374 y FC(\013)1663 2386 y FB(i)1713 2374 y Fy(=)23 b FC(\032)1844 2386 y FB(i)p FA(\000)p Fz(1)1957 2374 y FC(=)7 b Fy(~)-49 b FC(p)2041 2344 y Fz(\()p FB(i)p Fz(\))2116 2319 y Fn(T)2165 2374 y FC(q)2205 2344 y Fz(\()p FB(i)p Fz(\))1610 2478 y FC(x)1657 2448 y Fz(\()p FB(i)p Fz(\))1760 2478 y Fy(=)22 b FC(x)1894 2448 y Fz(\()p FB(i)p FA(\000)p Fz(1\))2078 2478 y Fy(+)c FC(\013)2214 2490 y FB(i)2242 2478 y FC(p)2284 2448 y Fz(\()p FB(i)p Fz(\))1610 2582 y FC(r)1649 2551 y Fz(\()p FB(i)p Fz(\))1752 2582 y Fy(=)23 b FC(r)1879 2551 y Fz(\()p FB(i)p FA(\000)p Fz(1\))2062 2582 y Fx(\000)18 b FC(\013)2198 2594 y FB(i)2226 2582 y FC(q)2266 2551 y Fz(\()p FB(i)p Fz(\))1613 2685 y Fy(~)-45 b FC(r)1649 2655 y Fz(\()p FB(i)p Fz(\))1752 2685 y Fy(=)26 b(~)-45 b FC(r)1879 2655 y Fz(\()p FB(i)p FA(\000)p Fz(1\))2062 2685 y Fx(\000)18 b FC(\013)2198 2697 y FB(i)2232 2685 y Fy(~)-48 b FC(q)2266 2655 y Fz(\()p FB(i)p Fz(\))1610 2785 y FG(check)19 b(con)m(v)o(er)o(gence;)d(continue)j(if)h(necessary) 1464 2884 y Fv(end)p 3717 3022 V 1020 3025 2700 4 v 1334 3180 a FG(Figure)f(2.7:)25 b(The)20 b(Preconditioned)d(BiConjugate)i (Gradient)h(Method)863 3472 y(In)28 b(a)h(parallel)f(en)m(vironment,)f (the)h(tw)o(o)g(matrix-v)o(ector)e(products)g(can)i(theoretically)f(be) h(performed)e(si-)739 3571 y(multaneously;)d(ho)n(we)n(v)o(er)m(,)f(in) h(a)h(distrib)n(uted-memory)c(en)m(vironment,)h(there)i(will)h(be)f(e)o (xtra)g(communication)739 3671 y(costs)j(associated)e(with)i(one)e(of)h 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b(=)g(\()t(~)-46 b FC(r)2139 5562 y Fz(\()p FB(i)p Fz(\))2220 5596 y FC(;)14 b(P)2322 5562 y Fz(2)2310 5617 y FB(i)2359 5596 y Fy(\()p FC(A)p Fy(\))p FC(r)2524 5562 y Fz(\(0\))2614 5596 y Fy(\))p FC(:)684 b FG(\(2.14\))p eop end %%Page: 22 32 TeXDict begin 22 31 bop 739 282 a FG(22)1825 b Fu(CHAPTER)21 b(2.)45 b(ITERA)-9 b(TIVE)19 b(METHODS)p 1010 757 2700 4 v 1010 4956 4 4200 v 1237 938 a FG(Compute)g FC(r)1601 908 y Fz(\(0\))1714 938 y Fy(=)j FC(b)d Fx(\000)f FC(Ax)2048 908 y Fz(\(0\))2158 938 y FG(for)i(some)g(initial)g(guess)g FC(x)2938 908 y Fz(\(0\))1240 1042 y Fy(~)-45 b FC(v)1280 1012 y Fz(\(1\))1392 1042 y Fy(=)23 b FC(r)1519 1012 y Fz(\(0\))1609 1042 y FG(;)d Fv(solv)o(e)h FC(M)1929 1054 y Fz(1)1965 1042 y FC(y)26 b Fy(=)g(~)-45 b FC(v)2163 1012 y Fz(\(1\))2252 1042 y FG(;)21 b FC(\032)2339 1054 y Fz(1)2399 1042 y Fy(=)i Fx(k)p FC(y)s Fx(k)2615 1054 y Fz(2)1237 1146 y FG(Choose)36 b Fy(~)-59 b FC(w)1567 1116 y Fz(\(1\))1678 1146 y FG(,)21 b(for)e(e)o(xample)36 b Fy(~)-59 b FC(w)2199 1116 y Fz(\(1\))2312 1146 y Fy(=)22 b FC(r)2438 1116 y Fz(\(0\))1237 1249 y Fv(solv)o(e)e FC(M)1522 1219 y FB(t)1513 1270 y Fz(2)1551 1249 y FC(z)26 b Fy(=)40 b(~)-59 b FC(w)1765 1219 y Fz(\(1\))1854 1249 y FG(;)21 b FC(\030)1934 1261 y Fz(1)1995 1249 y Fy(=)i Fx(k)p FC(z)t Fx(k)2210 1261 y Fz(2)1237 1349 y FC(\015)1280 1361 y Fz(0)1340 1349 y Fy(=)g(1;)14 b FC(\021)1548 1361 y Fz(0)1608 1349 y Fy(=)22 b Fx(\000)p Fy(1)1237 1449 y Fv(f)n(or)40 b FC(i)23 b Fy(=)f(1)p FC(;)14 b Fy(2)p FC(;)g(:)g(:)g(:)1382 1548 y Fv(if)21 b FC(\032)1497 1560 y FB(i)1547 1548 y Fy(=)i(0)d FG(or)g FC(\030)1823 1560 y FB(i)1874 1548 y Fy(=)j(0)d Fv(method)g(fails)1382 1652 y FC(v)1425 1622 y Fz(\()p FB(i)p Fz(\))1528 1652 y Fy(=)26 b(~)-45 b FC(v)1659 1622 y Fz(\()p FB(i)p Fz(\))1738 1652 y FC(=\032)1823 1664 y FB(i)1850 1652 y FG(;)21 b FC(y)26 b Fy(=)d FC(y)s(=\032)2178 1664 y FB(i)1382 1755 y FC(w)1443 1725 y Fz(\()p FB(i)p Fz(\))1546 1755 y Fy(=)40 b(~)-59 b FC(w)1695 1725 y Fz(\()p FB(i)p 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3054 y Fz(\()p FB(i)p Fz(\))1382 3188 y Fv(solv)o(e)i FC(M)1658 3200 y Fz(1)1695 3188 y FC(y)26 b Fy(=)g(~)-46 b FC(v)1892 3158 y Fz(\()p FB(i)p Fz(+1\))1382 3288 y FC(\032)1425 3300 y FB(i)p Fz(+1)1560 3288 y Fy(=)22 b Fx(k)p FC(y)s Fx(k)1775 3300 y Fz(2)1399 3391 y Fy(~)-59 b FC(w)1443 3361 y Fz(\()p FB(i)p Fz(+1\))1630 3391 y Fy(=)23 b FC(A)1780 3361 y FB(T)1833 3391 y FC(q)1873 3361 y Fz(\()p FB(i)p Fz(\))1971 3391 y Fx(\000)18 b FC(\014)2101 3403 y FB(i)2128 3391 y FC(w)2189 3361 y Fz(\()p FB(i)p Fz(\))1382 3495 y Fv(solv)o(e)i FC(M)1667 3465 y FB(T)1658 3515 y Fz(2)1719 3495 y FC(z)26 b Fy(=)40 b(~)-59 b FC(w)1933 3465 y Fz(\()p FB(i)p Fz(+1\))1382 3594 y FC(\030)1418 3606 y FB(i)p Fz(+1)1553 3594 y Fy(=)23 b Fx(k)p FC(z)t Fx(k)1768 3606 y Fz(2)1382 3703 y FC(\022)1421 3715 y FB(i)1472 3703 y Fy(=)f FC(\032)1602 3715 y FB(i)p Fz(+1)1714 3703 y FC(=)p Fy(\()p FC(\015)1831 3715 y FB(i)p FA(\000)p Fz(1)1943 3703 y Fx(j)p FC(\014)2013 3715 y FB(i)2041 3703 y Fx(j)p Fy(\))p FG(;)f 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FC(p)1819 4179 y Fz(\()p FB(i)p Fz(\))1916 4209 y Fy(+)18 b(\()p FC(\022)2070 4221 y FB(i)p FA(\000)p Fz(1)2183 4209 y FC(\015)2226 4221 y FB(i)2254 4209 y Fy(\))2286 4179 y Fz(2)2323 4209 y FC(d)2366 4179 y Fz(\()p FB(i)p FA(\000)p Fz(1\))1474 4312 y FC(s)1513 4282 y Fz(\()p FB(i)p Fz(\))1616 4312 y Fy(=)k FC(\021)1744 4324 y FB(i)1779 4312 y Fy(~)-49 b FC(p)19 b Fy(+)f(\()p FC(\022)1987 4324 y FB(i)p FA(\000)p Fz(1)2099 4312 y FC(\015)2142 4324 y FB(i)2170 4312 y Fy(\))2202 4282 y Fz(2)2240 4312 y FC(s)2279 4282 y Fz(\()p FB(i)p FA(\000)p Fz(1\))1382 4412 y Fv(endif)1382 4516 y FC(x)1429 4485 y Fz(\()p FB(i)p Fz(\))1532 4516 y Fy(=)23 b FC(x)1667 4485 y Fz(\()p FB(i)p FA(\000)p Fz(1\))1850 4516 y Fy(+)18 b FC(d)1976 4485 y Fz(\()p FB(i)p Fz(\))1382 4619 y FC(r)1421 4589 y Fz(\()p FB(i)p Fz(\))1524 4619 y Fy(=)23 b FC(r)1651 4589 y Fz(\()p FB(i)p FA(\000)p Fz(1\))1835 4619 y Fx(\000)18 b FC(s)1957 4589 y Fz(\()p FB(i)p Fz(\))1382 4719 y FG(check)h(con)m(v) o(er)o(gence;)e(continue)h(if)j(necessary)1237 4818 y Fv(end)p 3707 4956 4 4200 v 1010 4959 2700 4 v 947 5174 a FG(Figure)f(2.8:)k(The)c(Preconditioned)e(Quasi)i(Minimal)g(Residual) g(Method)f(without)h(Look-ahead)p eop end %%Page: 23 33 TeXDict begin 23 32 bop 291 282 a Fu(2.3.)45 b(NONST)-8 b(A)f(TION)m(AR)k(Y)19 b(ITERA)-9 b(TIVE)19 b(METHODS)1456 b FG(23)p 572 436 2700 4 v 572 2991 4 2556 v 1026 617 a(Compute)19 b FC(r)1390 587 y Fz(\(0\))1503 617 y Fy(=)k FC(b)18 b Fx(\000)g FC(Ax)1837 587 y Fz(\(0\))1948 617 y FG(for)h(some)h(initial)h(guess)f FC(x)2728 587 y Fz(\(0\))1026 721 y FG(Choose)k Fy(~)-46 b FC(r)24 b FG(\(for)19 b(e)o(xample,)j Fy(~)-46 b FC(r)26 b Fy(=)d FC(r)2013 691 y Fz(\(0\))2103 721 y FG(\))1026 820 y Fv(f)n(or)41 b FC(i)22 b Fy(=)h(1)p FC(;)14 b Fy(2)p FC(;)g(:)g(:)g(:)1172 924 y(\032)1215 936 y FB(i)p FA(\000)p Fz(1)1350 924 y Fy(=)27 b(~)-46 b FC(r)1477 894 y FB(T)1530 924 y FC(r)1569 894 y Fz(\()p FB(i)p FA(\000)p Fz(1\))1172 1024 y Fv(if)20 b FC(\032)1286 1036 y FB(i)p FA(\000)p Fz(1)1422 1024 y Fy(=)i(0)f Fv(method)f(fails) 1172 1123 y(if)41 b FC(i)23 b Fy(=)f(1)1264 1227 y FC(u)1312 1197 y Fz(\(1\))1424 1227 y Fy(=)g FC(r)1550 1197 y Fz(\(0\))1264 1331 y FC(p)1306 1300 y Fz(\(1\))1418 1331 y Fy(=)h FC(u)1554 1300 y Fz(\(1\))1172 1430 y Fv(else)1264 1530 y FC(\014)1311 1542 y FB(i)p FA(\000)p Fz(1)1447 1530 y Fy(=)f FC(\032)1577 1542 y FB(i)p FA(\000)p Fz(1)1690 1530 y FC(=\032)1775 1542 y FB(i)p FA(\000)p Fz(2)1264 1633 y FC(u)1312 1603 y Fz(\()p FB(i)p Fz(\))1414 1633 y Fy(=)h FC(r)1541 1603 y Fz(\()p FB(i)p FA(\000)p Fz(1\))1724 1633 y Fy(+)18 b FC(\014)1854 1645 y FB(i)p FA(\000)p Fz(1)1967 1633 y FC(q)2007 1603 y Fz(\()p FB(i)p FA(\000)p Fz(1\))1264 1737 y FC(p)1306 1707 y Fz(\()p FB(i)p Fz(\))1408 1737 y Fy(=)23 b FC(u)1544 1707 y Fz(\()p FB(i)p Fz(\))1641 1737 y Fy(+)18 b FC(\014)1771 1749 y FB(i)p FA(\000)p Fz(1)1884 1737 y Fy(\()p FC(q)1956 1707 y Fz(\()p FB(i)p FA(\000)p Fz(1\))2139 1737 y Fy(+)g FC(\014)2269 1749 y FB(i)p 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b(BiCG,)i(the)e(tw)o(o)h(matrix-v)o(ector)d(products) h(are)h(not)g(independent,)g(so)h(the)f(number)f(of)681 4286 y(synchronization)17 b(points)j(in)g(a)h(parallel)e(en)m (vironment)e(is)22 b(lar)o(ger)-5 b(.)394 4449 y(9.)41 b(Biconjugate)19 b(Gradient)g(Stabilized)h(\(Bi-CGST)-8 b(AB\))598 4612 y Fx(\017)41 b FG(Applicable)19 b(to)h(nonsymmetric)e (matrices.)598 4742 y Fx(\017)41 b FG(Computational)16 b(costs)i(per)g(iteration)f(are)h(similar)g(to)g(BiCG)h(and)e(CGS,)i(b) n(ut)f(the)g(method)e(doesn')o(t)681 4841 y(require)j(the)h(transpose)f (matrix.)598 4971 y Fx(\017)41 b FG(An)28 b(alternati)n(v)o(e)g(for)g (CGS)h(that)g(a)n(v)n(oids)g(the)f(irre)o(gular)f(con)m(v)o(er)o(gence) e(patterns)j(of)g(CGS)i(while)681 5071 y(maintaining)d(about)h(the)g (same)h(speed)g(of)f(con)m(v)o(er)o(gence;)h(as)h(a)f(result)g(we)g (often)f(observ)o(e)f(less)681 5171 y(loss)21 b(of)f(accurac)o(y)e(in)i (the)h(updated)d(residual.)353 5334 y(10.)40 b(Chebyshe)n(v)19 b(Iteration)598 5497 y Fx(\017)41 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b(Adapti)n(v)o(e)e(Chebyshe)n(v)h(method)f(can)i(be)g(used) f(in)h(combination)e(with)i(methods)f(as)i(CG)g(or)1129 1288 y(GMRES,)32 b(to)f(continue)f(the)h(iteration)g(once)g(suitable)g (bounds)f(on)h(the)g(spectrum)f(ha)n(v)o(e)h(been)1129 1387 y(obtained)19 b(from)g(these)h(methods.)863 1579 y(Selecting)i(the)g(\223best\224)g(method)f(for)g(a)h(gi)n(v)o(en)f (class)i(of)f(problems)e(is)j(lar)o(gely)e(a)h(matter)g(of)f(trial)i (and)e(error)-5 b(.)739 1678 y(It)19 b(also)g(depends)f(on)g(ho)n(w)g (much)g(storage)g(one)g(has)i(a)n(v)n(ailable)e(\(GMRES\),)g(on)h(the)g (a)n(v)n(ailability)f(of)g FC(A)3708 1648 y FB(T)3780 1678 y FG(\(BiCG)739 1778 y(and)29 b(QMR\),)i(and)e(on)h(ho)n(w)g(e)o (xpensi)n(v)o(e)e(the)i(matrix)g(v)o(ector)e(products)h(\(and)g(Solv)o (e)h(steps)h(with)f FC(M)9 b FG(\))30 b(are)g(in)739 1877 y(comparison)15 b(to)i FE(SAXPY)p FG(s)g(and)g(inner)f(products.) 23 b(If)17 b(these)g(matrix)g(v)o(ector)f(products)f(are)i(relati)n(v)o (ely)f(e)o(xpensi)n(v)o(e,)739 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b(that)g(conte)o(xt,)f(the)h(most)g(prominent)e (feature)h(of)h(the)g(method)e(is)j(that)g(it)739 3158 y(reduces)h(the)i(original)e(matrix)g(to)i(tridiagonal)e(form.)27 b(Lanczos)20 b(later)i(applied)e(his)i(method)e(to)h(solving)g(linear) 739 3258 y(systems,)29 b(in)e(particular)f(symmetric)g(ones)h([142)n (].)45 b(An)27 b(important)f(property)f(for)h(pro)o(ving)e(con)m(v)o (er)o(gence)g(of)739 3358 y(the)29 b(method)g(when)g(solving)f(linear)h (systems)h(is)h(that)f(the)f(iterates)h(are)f(related)h(to)f(the)h (initial)g(residual)f(by)739 3457 y(multiplication)19 b(with)h(a)h(polynomial)d(in)i(the)g(coef)n(\002cient)f(matrix.)863 3559 y(The)27 b(joint)f(paper)f(by)i(Hestenes)f(and)g(Stiefel)h([121)n (],)h(after)f(their)f(independent)e(disco)o(v)o(ery)g(of)j(the)f(same) 739 3659 y(method,)h(is)h(the)e(classical)i(description)d(of)i(the)g (conjugate)e(gradient)g(method)g(for)i(solving)f(linear)g(systems.)739 3758 y(Although)21 b(error)n(-reduction)e(properties)j(are)h(pro)o(v)o (ed,)e(and)h(e)o(xperiments)f(sho)n(wing)h(premature)f(con)m(v)o(er)o (gence)739 3858 y(are)27 b(reported,)g(the)h(conjugate)d(gradient)h (method)g(is)i(presented)f(here)f(as)i(a)g(direct)f(method,)h(rather)e (than)h(an)739 3957 y(iterati)n(v)o(e)19 b(method.)863 4059 y(This)25 b(Hestenes/Stiefel)f(method)e(is)j(closely)f(related)f (to)i(a)f(reduction)e(of)i(the)g(Lanczos)f(method)f(to)j(sym-)739 4159 y(metric)c(matrices,)h(reducing)e(the)h(tw)o(o)h(mutually)f (orthogonal)e(sequences)i(to)g(one)h(orthogonal)d(sequence,)h(b)n(ut) 739 4258 y(there)27 b(is)i(an)e(important)f(algorithmic)g(dif)n (ference.)46 b(Whereas)27 b(Lanczos)g(used)h(three-term)e(recurrences,) h(the)739 4358 y(method)d(by)h(Hestenes)h(and)e(Stiefel)i(uses)g (coupled)e(tw)o(o-term)g(recurrences.)39 b(By)26 b(combining)d(the)j (tw)o(o)f(tw)o(o-)739 4458 y(term)20 b(recurrences)e(\(eliminating)h (the)h(\223search)g(directions\224\))e(the)j(Lanczos)e(method)g(is)i (obtained.)863 4560 y(A)26 b(paper)f(by)g(Arnoldi)f([6)o(])i(further)d (discusses)j(the)g(Lanczos)e(biorthogonalization)d(method,)k(b)n(ut)h (it)g(also)739 4659 y(presents)i(a)h(ne)n(w)f(method,)g(combining)e (features)i(of)g(the)g(Lanczos)g(and)g(Hestenes/Stiefel)g(methods.)48 b(Lik)o(e)739 4759 y(the)24 b(Lanczos)f(method)g(it)i(is)g(applied)e (to)h(nonsymmetric)e(systems,)j(and)f(it)h(does)f(not)f(use)i(search)e (directions.)739 4858 y(Lik)o(e)h(the)g(Hestenes/Stiefel)h(method,)e (it)i(generates)f(only)f(one,)i(self-orthogonal)c(sequence.)36 b(This)24 b(last)h(f)o(act,)739 4958 y(combined)20 b(with)j(the)f (asymmetry)f(of)h(the)g(coef)n(\002cient)f(matrix)h(means)g(that)h(the) f(method)f(no)h(longer)f(ef)n(fects)h(a)739 5058 y(reduction)c(to)j (tridiagonal)e(form,)g(b)n(ut)h(instead)g(one)g(to)h(upper)e(Hessenber) o(g)f(form.)25 b(Presented)20 b(as)h(\223minimized)739 5157 y(iterations)f(in)g(the)g(Galerkin)f(method\224)g(this)i (algorithm)d(has)j(become)e(kno)n(wn)g(as)h(the)h Ft(Arnoldi)e (algorithm)p FG(.)863 5259 y(The)27 b(conjugate)f(gradient)g(method)g (recei)n(v)o(ed)g(little)i(attention)f(as)h(a)f(practical)g(method)f (for)h(some)g(time,)739 5359 y(partly)20 b(because)g(of)g(a)h (mispercei)n(v)o(ed)e(importance)f(of)j(the)f(\002nite)h(termination)e (property)-5 b(.)24 b(Reid)d([178)n(])g(pointed)p 739 5438 1306 4 v 829 5494 a FI(1)858 5517 y FJ(F)o(or)f(a)f(more)g (detailed)k(account)e(of)e(the)h(early)h(history)g(of)e(CG)g(methods,)h (we)g(refer)g(the)g(reader)h(to)e(Golub)h(and)g(O'Leary)g([107)q(])f (and)739 5596 y(Hestenes)f([122)q(].)p eop end %%Page: 31 41 TeXDict begin 31 40 bop 291 282 a Fu(2.6.)45 b(SUR)-7 b(VEY)21 b(OF)g(RECENT)f(KR)-5 b(YLO)l(V)20 b(METHODS)1433 b FG(31)291 515 y(out)26 b(that)h(the)g(most)g(important)e(application) g(area)i(lay)g(in)g(sparse)g(de\002nite)f(systems,)j(and)d(this)h(rene) n(wed)f(the)291 615 y(interest)20 b(in)g(the)g(method.)415 717 y(Se)n(v)o(eral)30 b(methods)g(ha)n(v)o(e)h(been)f(de)n(v)o(eloped) e(in)j(later)h(years)e(that)h(emplo)o(y)-5 b(,)32 b(most)f(often)f (implicitly)-5 b(,)33 b(the)291 816 y(upper)26 b(Hessenber)o(g)g (matrix)h(of)g(the)h(Arnoldi)e(method.)46 b(F)o(or)27 b(an)h(o)o(v)o(ervie)n(w)d(and)i(characterization)e(of)j(these)291 916 y(orthogonal)19 b(projection)h(methods)h(for)h(nonsymmetric)d (systems)k(see)g(Ashby)-5 b(,)21 b(Manteuf)n(fel)f(and)i(Saylor)f([10)o (],)291 1016 y(Saad)f(and)f(Schultz)h([187)n(],)h(and)e(Jea)i(and)f(Y) -9 b(oung)18 b([124)n(].)415 1118 y(Fletcher)e([97)n(])h(proposed)d(an) i(implementation)e(of)h(the)i(Lanczos)e(method,)g(similar)h(to)h(the)f (Conjugate)e(Gra-)291 1217 y(dient)22 b(method,)g(with)h(tw)o(o)g (coupled)e(tw)o(o-term)h(recurrences,)g(which)g(he)h(named)e(the)i Ft(bi-conjugate)d(gr)o(adient)291 1317 y(method)h FG(\(BiCG\).)291 1609 y Fs(2.6)119 b(Sur)o(v)o(ey)30 b(of)f(r)n(ecent)i(Krylo)o(v)e (methods)291 1799 y FG(Research)22 b(into)h(the)f(design)h(of)f(Krylo)o (v)f(subspace)h(methods)g(for)g(solving)g(nonsymmetric)e(linear)j (systems)g(is)291 1899 y(an)c(acti)n(v)o(e)f(\002eld)h(of)g(research)f (and)h(ne)n(w)g(methods)f(are)h(still)h(emer)o(ging.)i(In)d(this)h (book,)d(we)j(ha)n(v)o(e)e(included)g(only)291 1998 y(the)25 b(best)h(kno)n(wn)e(and)h(most)g(popular)f(methods,)i(and)f(in)g (particular)f(those)i(for)f(which)g(e)o(xtensi)n(v)o(e)f(computa-)291 2098 y(tional)f(e)o(xperience)f(has)i(been)f(gathered.)33 b(In)24 b(this)g(section,)g(we)g(shall)g(brie\003y)g(highlight)e(some)h (of)h(the)g(recent)291 2198 y(de)n(v)o(elopments)e(and)i(other)f (methods)h(not)g(treated)g(here.)38 b(A)25 b(surv)o(e)o(y)e(of)h (methods)g(up)g(to)h(about)e(1991)h(can)g(be)291 2297 y(found)f(in)i(Freund,)f(Golub)g(and)g(Nachtigal)g([105)n(].)39 b(T)-7 b(w)o(o)25 b(more)g(recent)f(reports)g(by)g(Meier)n(-Y)-8 b(ang)23 b([150)n(])i(and)291 2397 y(T)-7 b(ong)18 b([195)n(])h(ha)n(v) o(e)f(e)o(xtensi)n(v)o(e)f(numerical)h(comparisons)f(among)g(v)n 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Ft(Lanczos)d(br)m(eakdown) 291 4496 y FG(\(the)30 b(underlying)f(Lanczos)h(process)h(breaks)f(do)n (wn\),)j(and)d Ft(pivot)h(br)m(eakdown)f FG(\(the)g(tridiagonal)g (matrix)g FC(T)291 4595 y FG(implicitly)g(generated)f(in)i(the)f (underlying)e(Lanczos)i(process)g(encounters)f(a)j(zero)e(pi)n(v)n(ot)g (when)g(Gaussian)291 4695 y(elimination)19 b(without)g(pi)n(v)n(oting)g (is)i(used)f(to)h(f)o(actor)f(it\).)25 b(Although)19 b(such)h(e)o(xact)g(breakdo)n(wns)d(are)k(v)o(ery)e(rare)h(in)291 4795 y(practice,)f(near)g(breakdo)n(wns)f(can)i(cause)g(se)n(v)o(ere)g (numerical)f(stability)h(problems.)415 4897 y(The)29 b(pi)n(v)n(ot)f(breakdo)n(wn)f(is)j(the)f(easier)g(one)f(to)h(o)o(v)o (ercome)e(and)h(there)h(ha)n(v)o(e)f(been)h(se)n(v)o(eral)f(approaches) 291 4996 y(proposed)f(in)j(the)g(literature.)52 b(It)30 b(should)f(be)h(noted)e(that)i(for)f(symmetric)g(matrices,)j(Lanczos)d (breakdo)n(wn)291 5096 y(cannot)g(occur)h(and)h(the)g(only)f(possible)h 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615 y(and)d(Sadok)g([39)n(],)i(Brezinski,)e(Zaglia)h(and)f(Sadok)f([40) o(,)i(41)o(],)g(Freund)e(and)h(Nachtigal)g([101)n(],)h(P)o(arlett)g ([171)n(],)739 715 y(Nachtigal)38 b([159)o(],)44 b(Freund,)f(Gutknecht) 38 b(and)h(Nachtigal)g([100)n(],)45 b(Joubert)38 b([128)n(],)45 b(Freund,)e(Golub)c(and)739 814 y(Nachtigal)28 b([105)o(],)j(and)e (Gutknecht)f([112)o(,)h(115)o(]\).)53 b(Ho)n(we)n(v)o(er)m(,)30 b(the)f(resulting)g(algorithms)f(are)i(usually)f(too)739 914 y(complicated)35 b(to)i(gi)n(v)o(e)f(in)h(template)f(form)g(\(some) g(codes)g(of)g(Freund)g(and)g(Nachtigal)g(are)g(a)n(v)n(ailable)h(on) 739 1013 y FE(netlib)p FG(.\))69 b(Moreo)o(v)o(er)m(,)36 b(it)g(is)g(still)g(not)f(possible)g(to)g(eliminate)g(breakdo)n(wns)e (that)i(require)f(look-ahead)739 1113 y(steps)24 b(of)g(arbitrary)e (size)j(\(incurable)d(breakdo)n(wns\).)34 b(So)24 b(f)o(ar)m(,)g(these) g(methods)f(ha)n(v)o(e)g(not)h(yet)g(recei)n(v)o(ed)e(much)739 1213 y(practical)d(use)g(b)n(ut)g(some)h(form)e(of)h(look-ahead)e(may)h (pro)o(v)o(e)g(to)h(be)h(a)f(crucial)g(component)e(in)i(future)g (methods.)863 1312 y(In)29 b(the)g(BiCG)i(method,)e(the)g(need)g(for)f (matrix-v)o(ector)e(multiplies)j(with)h FC(A)3144 1282 y FB(T)3226 1312 y FG(can)f(be)g(incon)m(v)o(enient)d(as)739 1412 y(well)g(as)h(doubling)d(the)i(number)e(of)i(matrix-v)o(ector)d (multiplies)j(compared)e(with)i(CG)h(for)f(each)f(increase)h(in)739 1512 y(the)19 b(de)o(gree)e(of)h(the)h(underlying)d(Krylo)o(v)h (subspace.)24 b(Se)n(v)o(eral)18 b(recent)g(methods)g(ha)n(v)o(e)g (been)g(proposed)f(to)i(o)o(v)o(er)n(-)739 1611 y(come)i(this)i(dra)o (wback.)28 b(The)21 b(most)h(notable)f(of)h(these)g(is)h(the)f (ingenious)e(CGS)j(method)e(by)g(Sonne)n(v)o(eld)f([191)n(])739 1711 y(discussed)f(earlier)m(,)g(which)g(computes)f(the)h(square)g(of)g (the)h(BiCG)h(polynomial)c(without)i(requiring)e FC(A)3729 1681 y FB(T)3802 1711 y FG(\226)i(thus)739 1810 y(ob)o(viating)k(the)i (need)f(for)g FC(A)1570 1780 y FB(T)1623 1810 y FG(.)39 b(When)25 b(BiCG)h(con)m(v)o(er)o(ges,)d(CGS)j(is)g(often)e(an)h (attracti)n(v)o(e,)g(f)o(aster)g(con)m(v)o(er)o(ging)739 1910 y(alternati)n(v)o(e.)40 b(Ho)n(we)n(v)o(er)m(,)24 b(CGS)j(also)f(inherits)f(\(and)f(often)h(magni\002es\))g(the)g (breakdo)n(wn)e(conditions)h(and)h(the)739 2010 y(irre)o(gular)18 b(con)m(v)o(er)o(gence)e(of)k(BiCG)i(\(see)e(V)-9 b(an)20 b(der)g(V)-11 b(orst)20 b([205)o(]\).)863 2109 y(CGS)35 b(also)f(generated)e(interest)h(in)h(the)f(possibility)h(of)f Ft(pr)l(oduct)h FG(methods,)i(which)d(generate)f(iterates)739 2209 y(corresponding)d(to)k(a)h(product)d(of)h(the)h(BiCG)h(polynomial) d(with)i(another)e(polynomial)g(of)i(the)g(same)g(de-)739 2309 y(gree,)g(chosen)c(to)i(ha)n(v)o(e)g(certain)f(desirable)g (properties)f(b)n(ut)i(computable)e(without)h(recourse)g(to)h FC(A)3742 2278 y FB(T)3794 2309 y FG(.)58 b(The)739 2408 y(Bi-CGST)-8 b(AB)21 b(method)d(of)h(V)-9 b(an)19 b(der)g(V)-11 b(orst)20 b([205)n(])g(is)g(such)g(an)f(e)o(xample,)f(in)i(which)f(the) g(auxiliary)f(polynomial)739 2508 y(is)26 b(de\002ned)f(by)g(a)h(local) f(minimization)f(chosen)g(to)i(smooth)f(the)g(con)m(v)o(er)o(gence)c (beha)n(vior)-5 b(.)40 b(Gutknecht)24 b([114)n(])739 2607 y(noted)e(that)h(Bi-CGST)-8 b(AB)25 b(could)d(be)h(vie)n(wed)f(as) i(a)g(product)d(of)i(BiCG)h(and)f(GMRES\(1\),)g(and)f(he)h(suggested) 739 2707 y(combining)f(BiCG)j(with)f(GMRES\(2\))f(for)h(the)g(e)n(v)o (en)f(numbered)e(iteration)i(steps.)37 b(This)24 b(w)o(as)h (anticipated)e(to)739 2807 y(lead)g(to)g(better)f(con)m(v)o(er)o(gence) d(for)k(the)g(case)g(where)f(the)h(eigen)m(v)n(alues)e(of)i FC(A)h FG(are)f(comple)o(x.)31 b(A)24 b(more)e(ef)n(\002cient)739 2906 y(and)k(more)f(rob)n(ust)h(v)n(ariant)f(of)h(this)h(approach)d (has)i(been)g(suggested)f(by)h(Sleijpen)g(and)g(F)o(okk)o(ema)f(in)h ([189)n(],)739 3006 y(where)19 b(the)o(y)h(describe)f(ho)n(w)h(to)g (easily)h(combine)d(BiCG)k(with)e(an)o(y)g(GMRES\()p FC(m)p FG(\),)f(for)h(modest)g FC(m)p FG(.)863 3106 y(Man)o(y)27 b(other)g(basic)h(methods)e(can)i(also)g(be)f(squared.)46 b(F)o(or)28 b(e)o(xample,)f(by)h(squaring)e(the)i(Lanczos)e(pro-)739 3205 y(cedure,)f(Chan,)h(de)f(Pillis)h(and)f(V)-9 b(an)24 b(der)h(V)-11 b(orst)25 b([45)o(])g(obtained)f(transpose-free)f (implementations)g(of)i(BiCG)739 3305 y(and)d(QMR.)h(By)h(squaring)d (the)i(QMR)h(method,)d(Freund)h(and)g(Szeto)h([103)n(])h(deri)n(v)o(ed) d(a)i(transpose-free)e(QMR)739 3404 y(squared)h(method)g(which)h(is)i (quite)e(competiti)n(v)o(e)f(with)h(CGS)i(b)n(ut)e(with)h(much)f (smoother)f(con)m(v)o(er)o(gence.)31 b(Un-)739 3504 y(fortunately)-5 b(,)26 b(these)h(methods)f(require)f(an)i(e)o(xtra)g(matrix-v)o(ector)d (product)h(per)h(step)i(\(three)e(instead)h(of)f(tw)o(o\))739 3604 y(which)20 b(mak)o(es)g(them)f(less)j(ef)n(\002cient.)863 3703 y(In)h(addition)e(to)i(Bi-CGST)-8 b(AB,)23 b(se)n(v)o(eral)f (recent)g(product)f(methods)g(ha)n(v)o(e)h(been)g(designed)f(to)i (smooth)e(the)739 3803 y(con)m(v)o(er)o(gence)26 b(of)31 b(CGS.)g(One)f(idea)h(is)g(to)g(use)g(the)f(quasi-minimal)f(residual)h (\(QMR\))g(principle)f(to)i(obtain)739 3903 y(smoothed)26 b(iterates)i(from)e(the)i(Krylo)o(v)e(subspace)g(generated)g(by)h (other)g(product)f(methods.)46 b(Freund)26 b([104)n(])739 4002 y(proposed)g(such)i(a)g(QMR)h(v)o(ersion)d(of)i(CGS,)h(which)e(he) h(called)g(TFQMR.)g(Numerical)f(e)o(xperiments)f(sho)n(w)739 4102 y(that)c(TFQMR)h(in)g(most)g(cases)g(retains)f(the)h(desirable)e (con)m(v)o(er)o(gence)e(features)i(of)i(CGS)g(while)g(correcting)d(its) 739 4201 y(erratic)i(beha)n(vior)-5 b(.)32 b(The)23 b(transpose)f(free) g(nature)g(of)g(TFQMR,)i(its)g(lo)n(w)e(computational)f(cost)i(and)f (its)i(smooth)739 4301 y(con)m(v)o(er)o(gence)18 b(beha)n(vior)i(mak)o (e)h(it)i(an)f(attracti)n(v)o(e)f(alternati)n(v)o(e)f(to)i(CGS.)h(On)e (the)h(other)f(hand,)g(since)h(the)g(BiCG)739 4401 y(polynomial)14 b(is)k(still)g(used,)e(TFQMR)i(breaks)d(do)n(wn)h(whene)n(v)o(er)e(CGS) k(does.)24 b(One)16 b(possible)g(remedy)f(w)o(ould)h(be)739 4500 y(to)k(combine)e(TFQMR)i(with)f(a)h(look-ahead)d(Lanczos)i (technique)f(b)n(ut)h(this)h(appears)f(to)g(be)h(quite)f(complicated) 739 4600 y(and)h(no)g(methods)f(of)i(this)g(kind)f(ha)n(v)o(e)f(yet)i (appeared)e(in)h(the)h(literature.)k(Recently)-5 b(,)20 b(Chan)g Ft(et.)h(al.)g FG([46)n(])g(deri)n(v)o(ed)739 4700 y(a)26 b(similar)h(QMR)f(v)o(ersion)f(of)h(V)-9 b(an)26 b(der)f(V)-11 b(orst')-5 b(s)27 b(Bi-CGST)-8 b(AB)28 b(method,)e(which)f(is)i(called)f(QMRCGST)-8 b(AB.)739 4799 y(These)20 b(methods)f(of)n(fer)g(smoother)g(con)m(v)o (er)o(gence)d(o)o(v)o(er)j(CGS)i(and)f(Bi-CGST)-8 b(AB)21 b(with)g(little)g(additional)e(cost.)863 4899 y(There)30 b(is)i(no)e(clear)h(best)g(Krylo)o(v)e(subspace)h(method)g(at)h(this)g (time,)j(and)c(there)g(will)i(ne)n(v)o(er)d(be)i(a)g(best)739 4998 y Ft(o)o(ver)o(all)21 b FG(Krylo)o(v)e(subspace)h(method.)26 b(Each)21 b(of)g(the)g(methods)e(is)j(a)g(winner)e(in)h(a)g(speci\002c) h(problem)d(class,)j(and)739 5098 y(the)g(main)g(problem)e(is)j(to)g (identify)e(these)h(classes)i(and)d(to)i(construct)e(ne)n(w)h(methods)f (for)g(unco)o(v)o(ered)e(classes.)739 5198 y(The)f(paper)g(by)g (Nachtigal,)g(Reddy)g(and)g(T)m(refethen)f([157)n(])i(sho)n(ws)g(that)g (for)f(an)o(y)f(of)i(a)g(group)e(of)h(methods)g(\(CG,)739 5297 y(BiCG,)27 b(GMRES,)e(CGNE,)h(and)f(CGS\),)h(there)f(is)i(a)f (class)g(of)f(problems)f(for)h(which)g(a)h(gi)n(v)o(en)f(method)f(is)i (the)739 5397 y(winner)20 b(and)g(another)g(one)g(is)i(the)f(loser)-5 b(.)27 b(This)21 b(sho)n(ws)g(clearly)g(that)g(there)f(will)i(be)f(no)f (ultimate)h(method.)26 b(The)739 5497 y(best)c(we)f(can)h(hope)e(for)h (is)h(some)f(e)o(xpert)f(system)i(that)f(guides)g(the)g(user)h(in)f (his/her)g(choice.)28 b(Hence,)21 b(iterati)n(v)o(e)739 5596 y(methods)j(will)j(ne)n(v)o(er)d(reach)h(the)g(rob)n(ustness)g(of) h(direct)f(methods,)h(nor)e(will)j(the)o(y)e(beat)g(direct)g(methods)g (for)p eop end %%Page: 33 43 TeXDict begin 33 42 bop 291 282 a Fu(2.6.)45 b(SUR)-7 b(VEY)21 b(OF)g(RECENT)f(KR)-5 b(YLO)l(V)20 b(METHODS)1433 b FG(33)291 515 y(all)24 b(problems.)34 b(F)o(or)24 b(some)f(problems,) g(iterati)n(v)o(e)h(schemes)f(will)i(be)e(most)h(attracti)n(v)o(e,)g (and)f(for)g(others,)h(direct)291 615 y(methods)18 b(\(or)h (multigrid\).)k(W)-7 b(e)21 b(hope)e(to)h(\002nd)f(suitable)h(methods)e (\(and)h(preconditioners\))e(for)i(classes)i(of)e(v)o(ery)291 715 y(lar)o(ge)f(problems)g(that)h(we)h(are)f(yet)h(unable)e(to)i(solv) o(e)e(by)h(an)o(y)g(kno)n(wn)f(method,)g(because)g(of)i (CPU-restrictions,)291 814 y(memory)-5 b(,)17 b(con)m(v)o(er)o(gence)g (problems,)h(ill-conditioning,)f(et)k(cetera.)p eop end %%Page: 34 44 TeXDict begin 34 43 bop 739 282 a FG(34)1825 b Fu(CHAPTER)21 b(2.)45 b(ITERA)-9 b(TIVE)19 b(METHODS)p eop end %%Page: 35 45 TeXDict begin 35 44 bop 291 1138 a FD(Chapter)44 b(3)291 1553 y FF(Pr)l(econditioners)291 2035 y Fs(3.1)119 b(The)30 b(wh)n(y)g(and)h(ho)o(w)291 2220 y FG(The)20 b(con)m(v)o(er)o(gence)c (rate)21 b(of)f(iterati)n(v)o(e)g(methods)g(depends)f(on)h(spectral)g (properties)f(of)i(the)f(coef)n(\002cient)g(matrix.)291 2320 y(Hence)e(one)g(may)g(attempt)g(to)g(transform)f(the)i(linear)f (system)h(into)f(one)g(that)g(is)i(equi)n(v)n(alent)d(in)h(the)h(sense) g(that)f(it)291 2419 y(has)h(the)g(same)g(solution,)f(b)n(ut)h(that)g (has)h(more)e(f)o(a)n(v)n(orable)g(spectral)h(properties.)k(A)c Ft(pr)m(econditioner)g FG(is)h(a)g(matrix)291 2519 y(that)g(ef)n(fects) g(such)g(a)g(transformation.)415 2619 y(F)o(or)d(instance,)g(if)g(a)h (matrix)e FC(M)26 b FG(approximates)15 b(the)j(coef)n(\002cient)e (matrix)g FC(A)i FG(in)f(some)g(w)o(ay)-5 b(,)17 b(the)g(transformed) 291 2718 y(system)498 2867 y FC(M)588 2832 y FA(\000)p Fz(1)677 2867 y FC(Ax)24 b Fy(=)e FC(M)987 2832 y FA(\000)p Fz(1)1076 2867 y FC(b)291 3015 y FG(has)i(the)g(same)g(solution)f(as)i (the)f(original)f(system)h FC(Ax)31 b Fy(=)f FC(b)p FG(,)25 b(b)n(ut)f(the)g(spectral)g(properties)e(of)i(its)h(coef)n(\002cient) 291 3115 y(matrix)19 b FC(M)618 3085 y FA(\000)p Fz(1)707 3115 y FC(A)i FG(may)f(be)g(more)f(f)o(a)n(v)n(orable.)415 3214 y(In)32 b(de)n(vising)f(a)h(preconditioner)m(,)g(we)g(are)g(f)o (aced)g(with)g(a)h(choice)e(between)h(\002nding)f(a)h(matrix)g FC(M)41 b FG(that)291 3314 y(approximates)28 b FC(A)p FG(,)35 b(and)30 b(for)g(which)h(solving)f(a)h(system)g(is)h(easier)f (than)g(solving)f(one)g(with)h FC(A)p FG(,)j(or)d(\002nding)291 3414 y(a)e(matrix)f FC(M)39 b FG(that)29 b(approximates)e FC(A)1416 3383 y FA(\000)p Fz(1)1505 3414 y FG(,)32 b(so)d(that)g(only) g(multiplication)e(by)i FC(M)38 b FG(is)30 b(needed.)50 b(The)29 b(majority)291 3513 y(of)h(preconditioners)e(f)o(alls)k(in)f (the)g(\002rst)g(cate)o(gory;)k(a)c(notable)f(e)o(xample)g(of)g(the)h (second)f(cate)o(gory)f(will)j(be)291 3613 y(discussed)20 b(in)g Fx(x)p FG(3.5.)291 3847 y Fp(3.1.1)98 b(Cost)25 b(trade-off)291 4002 y FG(Since)i(using)f(a)h(preconditioner)d(in)j(an) g(iterati)n(v)o(e)g(method)e(incurs)i(some)f(e)o(xtra)h(cost,)h(both)f (initially)g(for)f(the)291 4102 y(setup,)i(and)f(per)g(iteration)g(for) g(applying)f(it,)j(there)e(is)i(a)f(trade-of)n(f)d(between)i(the)g (cost)h(of)f(constructing)e(and)291 4201 y(applying)17 b(the)j(preconditioner)m(,)c(and)j(the)h(gain)e(in)i(con)m(v)o(er)o (gence)c(speed.)24 b(Certain)c(preconditioners)c(need)j(little)291 4301 y(or)31 b(no)g(construction)e(phase)i(at)h(all)f(\(for)g(instance) g(the)g(SSOR)i(preconditioner\),)d(b)n(ut)h(for)g(others,)i(such)e(as) 291 4401 y(incomplete)d(f)o(actorizations,)i(there)f(can)h(be)g (substantial)f(w)o(ork)g(in)m(v)n(olv)o(ed.)51 b(Although)28 b(the)i(w)o(ork)f(in)h(scalar)291 4500 y(terms)24 b(may)g(be)h (comparable)d(to)j(a)g(single)f(iteration,)h(the)g(construction)d(of)j (the)f(preconditioner)e(may)i(not)g(be)291 4600 y(v)o (ectorizable/parallelizable)18 b(e)n(v)o(en)i(if)i(application)e(of)i (the)g(preconditioner)c(is.)30 b(In)22 b(that)g(case,)g(the)g(initial)g (cost)291 4700 y(has)e(to)g(be)g(amortized)e(o)o(v)o(er)h(the)h (iterations,)f(or)h(o)o(v)o(er)e(repeated)h(use)h(of)g(the)g(same)g (preconditioner)c(in)21 b(multiple)291 4799 y(linear)e(systems.)415 4899 y(Most)25 b(preconditioners)d(tak)o(e)j(in)g(their)g(application)e (an)i(amount)f(of)g(w)o(ork)h(proportional)d(to)j(the)g(number)291 4998 y(of)h(v)n(ariables.)44 b(This)27 b(implies)g(that)f(the)o(y)g (multiply)g(the)h(w)o(ork)f(per)g(iteration)g(by)h(a)g(constant)f(f)o (actor)-5 b(.)44 b(On)27 b(the)291 5098 y(other)20 b(hand,)h(the)h (number)d(of)j(iterations)f(as)h(a)g(function)e(of)h(the)h(matrix)f (size)h(is)h(usually)e(only)f(impro)o(v)o(ed)f(by)i(a)291 5198 y(constant.)30 b(Certain)23 b(preconditioners)c(are)k(able)f(to)h (impro)o(v)o(e)d(on)i(this)h(situation,)f(most)h(notably)e(the)h (modi\002ed)291 5297 y(incomplete)c(f)o(actorizations)h(and)h (preconditioners)d(based)j(on)g(multigrid)e(techniques.)415 5397 y(On)29 b(parallel)f(machines)g(there)g(is)i(a)f(further)e (trade-of)n(f)g(between)g(the)i(ef)n(\002cac)o(y)f(of)g(a)h (preconditioner)d(in)291 5497 y(the)21 b(classical)h(sense,)g(and)f (its)i(parallel)e(ef)n(\002cienc)o(y)-5 b(.)27 b(Man)o(y)20 b(of)i(the)f(traditional)g(preconditioners)d(ha)n(v)o(e)j(a)h(lar)o(ge) 291 5596 y(sequential)d(component.)1880 5806 y(35)p eop end %%Page: 36 46 TeXDict begin 36 45 bop 739 282 a FG(36)1905 b Fu(CHAPTER)21 b(3.)46 b(PRECONDITIONERS)739 515 y Fp(3.1.2)99 b(Left)26 b(and)f(right)g(pr)n(econditioning)739 684 y FG(The)e(abo)o(v)o(e)f (transformation)f(of)j(the)g(linear)f(system)h FC(A)30 b Fx(!)f FC(M)2607 653 y FA(\000)p Fz(1)2696 684 y FC(A)c FG(is)f(often)f(not)g(what)h(is)h(used)e(in)h(practice.)739 783 y(F)o(or)19 b(instance,)g(the)h(matrix)f FC(M)1635 753 y FA(\000)p Fz(1)1723 783 y FC(A)i FG(is)f(not)g(symmetric,)e(so,)i (e)n(v)o(en)f(if)h FC(A)g FG(and)f FC(M)29 b FG(are,)19 b(the)h(conjugate)d(gradients)739 883 y(method)j(is)i(not)g (immediately)e(applicable)g(to)i(this)g(system.)29 b(The)21 b(method)f(as)j(described)d(in)h(\002gure)g(2.5)g(reme-)739 982 y(dies)j(this)g(by)g(emplo)o(ying)e(the)h FC(M)1743 952 y FA(\000)p Fz(1)1832 982 y FG(-inner)g(product)f(for)h (orthogonalization)d(of)k(the)f(residuals.)36 b(The)24 b(theory)739 1082 y(of)c(the)g(cg)g(method)f(is)i(then)f(applicable)f (again.)863 1188 y(All)25 b(cg-type)d(methods)g(in)i(this)g(book,)f (with)h(the)g(e)o(xception)d(of)j(QMR,)g(ha)n(v)o(e)f(been)g(deri)n(v)o (ed)f(with)h(such)h(a)739 1288 y(combination)18 b(of)i(preconditioned)c (iteration)k(matrix)f(and)h(correspondingly)c(changed)j(inner)g (product.)863 1394 y(Another)k(w)o(ay)h(of)f(deri)n(ving)f(the)i (preconditioned)c(conjugate)h(gradients)i(method)f(w)o(ould)h(be)h(to)g (split)g(the)739 1494 y(preconditioner)17 b(as)k FC(M)31 b Fy(=)23 b FC(M)1615 1506 y Fz(1)1652 1494 y FC(M)1733 1506 y Fz(2)1790 1494 y FG(and)d(to)g(transform)f(the)h(system)g(as)946 1686 y FC(M)1036 1651 y FA(\000)p Fz(1)1027 1708 y(1)1125 1686 y FC(AM)1277 1651 y FA(\000)p Fz(1)1268 1708 y(2)1366 1686 y Fy(\()p FC(M)1479 1698 y Fz(2)1516 1686 y FC(x)p Fy(\))k(=)f FC(M)1797 1651 y FA(\000)p Fz(1)1788 1708 y(1)1885 1686 y FC(b:)739 1872 y FG(If)28 b FC(M)38 b FG(is)29 b(symmetric)e(and)h FC(M)1635 1884 y Fz(1)1710 1872 y Fy(=)38 b FC(M)1903 1842 y FB(t)1894 1893 y Fz(2)1932 1872 y FG(,)30 b(it)f(is)h(ob)o(vious)c(that)j(we)g(no)n(w)e(ha)n(v)o (e)h(a)h(method)e(with)h(a)h(symmetric)739 1972 y(iteration)19 b(matrix,)h(hence)f(the)h(conjugate)e(gradients)h(method)g(can)h(be)g (applied.)863 2078 y(Remarkably)-5 b(,)19 b(the)j(splitting)e(of)h FC(M)31 b FG(is)22 b(in)f(practice)f(not)h(needed.)26 b(By)c(re)n(writing)e(the)h(steps)h(of)e(the)i(method)739 2178 y(\(see)i(for)f(instance)h(Ax)o(elsson)f(and)g(Bark)o(er)h([14)n (,)i(pgs.)d(16,29])f(or)i(Golub)f(and)g(V)-9 b(an)23 b(Loan)g([108)o(,)i Fx(x)p FG(10.3]\))d(it)i(is)739 2277 y(usually)19 b(possible)h(to)h(reintroduce)d(a)i(computational)e(step) 946 2470 y(solv)o(e)i FC(u)h FG(from)e FC(M)9 b(u)22 b Fy(=)g FC(v)t(;)739 2656 y FG(that)e(is,)h(a)g(step)f(that)g(applies) g(the)h(preconditioner)c(in)j(its)h(entirety)-5 b(.)863 2762 y(There)16 b(is)i(a)f(dif)n(ferent)e(approach)f(to)j (preconditioning,)c(which)j(is)i(much)d(easier)i(to)g(deri)n(v)o(e.)22 b(Consider)16 b(again)739 2861 y(the)k(system.)946 3054 y FC(M)1036 3018 y FA(\000)p Fz(1)1027 3076 y(1)1125 3054 y FC(AM)1277 3018 y FA(\000)p Fz(1)1268 3076 y(2)1366 3054 y Fy(\()p FC(M)1479 3066 y Fz(2)1516 3054 y FC(x)p Fy(\))k(=)f FC(M)1797 3018 y FA(\000)p Fz(1)1788 3076 y(1)1885 3054 y FC(b:)739 3240 y FG(The)i(matrices)g FC(M)1282 3252 y Fz(1)1345 3240 y FG(and)g FC(M)1572 3252 y Fz(2)1635 3240 y FG(are)g(called)h(the)f Ft(left-)h FG(and)f Ft(right)g(pr)m(econditioner)o(s)p FG(,)g(respecti)n(v)o(ely) -5 b(,)25 b(and)g(we)g(can)739 3339 y(simp)o(y)31 b(apply)f(an)h (unpreconditioned)26 b(iterati)n(v)o(e)31 b(method)e(to)j(this)f (system.)58 b(Only)30 b(tw)o(o)i(additional)d(actions)739 3439 y FC(r)776 3451 y Fz(0)837 3439 y Fx( )23 b FC(M)1033 3403 y FA(\000)p Fz(1)1024 3461 y(1)1121 3439 y FC(r)1158 3451 y Fz(0)1217 3439 y FG(before)c(the)h(iterati)n(v)o(e)f(process)h (and)g FC(x)2319 3451 y FB(n)2387 3439 y Fx( )k FC(M)2584 3403 y FA(\000)p Fz(1)2575 3461 y(2)2672 3439 y FC(x)2719 3451 y FB(n)2786 3439 y FG(after)c(are)g(necessary)-5 b(.)863 3545 y(Thus)33 b(we)h(arri)n(v)o(e)e(at)i(the)f(follo)n(wing)e (schematic)i(for)g(deri)n(ving)e(a)j(left/right)e(preconditioned)e (iterati)n(v)o(e)739 3645 y(method)19 b(from)g(an)o(y)g(of)h(the)g (symmetrically)f(preconditioned)e(methods)i(in)h(this)h(book.)843 3831 y(1.)40 b(T)-7 b(ak)o(e)21 b(a)f(preconditioned)d(iterati)n(v)o(e) j(method,)e(and)i(replace)f(e)n(v)o(ery)g(occurence)f(of)i FC(M)30 b FG(by)19 b FC(I)7 b FG(.)843 4023 y(2.)40 b(Remo)o(v)o(e)19 b(an)o(y)h(v)o(ectors)f(from)g(the)h(algorithm)f(that)h(ha)n(v)o(e)g (become)f(duplicates)g(in)i(the)f(pre)n(vious)e(step.)843 4216 y(3.)40 b(Replace)21 b(e)n(v)o(ery)d(occurrence)g(of)i FC(A)h FG(in)g(the)f(method)f(by)g FC(M)2665 4180 y FA(\000)p Fz(1)2656 4238 y(1)2754 4216 y FC(AM)2906 4180 y FA(\000)p Fz(1)2897 4238 y(2)2995 4216 y FG(.)843 4408 y(4.)40 b(After)20 b(the)h(calculation)e(of)h(the)g(initial)g(residual,)g(add)f (the)h(step)1154 4634 y FC(r)1191 4646 y Fz(0)1252 4634 y Fx( )j FC(M)1448 4598 y FA(\000)p Fz(1)1439 4656 y(1)1537 4634 y FC(r)1574 4646 y Fz(0)1611 4634 y FC(:)843 4859 y FG(5.)40 b(At)21 b(the)f(end)g(of)g(the)g(method,)f(add)g(the)i(step) 1154 5085 y FC(x)j Fx( )f FC(M)1421 5050 y FA(\000)p Fz(1)1412 5107 y(2)1509 5085 y FC(x;)946 5311 y FG(where)d FC(x)h FG(is)g(the)g(\002nal)f(calculated)f(solution.)739 5497 y(It)d(should)f(be)h(noted)f(that)h(such)g(methods)f(cannot)g(be)h (made)f(to)h(reduce)f(to)h(the)g(algorithms)f(gi)n(v)o(en)g(in)h (section)g(2.3)739 5596 y(by)k(such)g(choices)f(as)i FC(M)1456 5608 y Fz(1)1516 5596 y Fy(=)i FC(M)1694 5566 y FB(t)1685 5617 y Fz(2)1743 5596 y FG(or)d FC(M)1914 5608 y Fz(1)1974 5596 y Fy(=)j FC(I)7 b FG(.)p eop end %%Page: 37 47 TeXDict begin 37 46 bop 291 282 a Fu(3.2.)45 b(J)-5 b(A)m(COBI)21 b(PRECONDITIONING)1943 b FG(37)291 515 y Fs(3.2)119 b(J)n(acobi)30 b(Pr)n(econditioning)291 701 y FG(The)19 b(simplest)i(preconditioner)c (consists)k(of)f(just)g(the)g(diagonal)f(of)h(the)g(matrix:)498 911 y FC(m)571 923 y FB(i;j)672 911 y Fy(=)760 794 y Fw(\032)864 861 y FC(a)908 873 y FB(i;i)1061 861 y FG(if)h FC(i)i Fy(=)f FC(j)864 960 y Fy(0)155 b FG(otherwise)o FC(:)291 1119 y FG(This)20 b(is)h(kno)n(wn)e(as)i(the)f(\(point\))f (Jacobi)g(preconditioner)-5 b(.)415 1219 y(It)17 b(is)g(possible)f(to)g (use)h(this)f(preconditioner)d(without)j(using)g(an)o(y)f(e)o(xtra)h (storage)f(be)o(yond)f(that)i(of)g(the)h(matrix)291 1318 y(itself.)32 b(Ho)n(we)n(v)o(er)m(,)21 b(di)n(vision)h(operations)f (are)h(usually)g(quite)g(costly)-5 b(,)23 b(so)g(in)f(practice)g (storage)g(is)i(allocated)e(for)291 1418 y(the)e(reciprocals)f(of)h (the)g(matrix)f(diagonal.)24 b(This)c(strate)o(gy)g(applies)f(to)i(man) o(y)e(preconditioners)e(belo)n(w)-5 b(.)291 1655 y Fp(3.2.1)98 b(Block)26 b(J)o(acobi)e(Methods)291 1811 y FG(Block)19 b(v)o(ersions)g(of)g(the)h(Jacobi)f(preconditioner)e(can)i(be)h(deri)n (v)o(ed)e(by)h(a)h(partitioning)e(of)i(the)f(v)n(ariables.)24 b(If)c(the)291 1910 y(inde)o(x)f(set)i FC(S)27 b Fy(=)c Fx(f)p Fy(1)p FC(;)14 b(:)g(:)g(:)f(;)h(n)p Fx(g)20 b FG(is)h(partitioned)d(as)j FC(S)28 b Fy(=)1866 1848 y Fw(S)1936 1935 y FB(i)1977 1910 y FC(S)2028 1922 y FB(i)2076 1910 y FG(with)21 b(the)f(sets)h FC(S)2563 1922 y FB(i)2612 1910 y FG(mutually)e(disjoint,)g(then)498 2128 y FC(m)571 2140 y FB(i;j)672 2128 y Fy(=)760 2011 y Fw(\032)864 2077 y FC(a)908 2089 y FB(i;j)1069 2077 y FG(if)h FC(i)h FG(and)e FC(j)26 b FG(are)20 b(in)g(the)h(same)f(inde)o(x)f(subset)864 2177 y Fy(0)163 b FG(otherwise)o FC(:)291 2335 y FG(The)19 b(preconditioner)e(is)k(no)n(w)f(a)h(block-diagonal)c(matrix.)415 2435 y(Often,)j(natural)f(choices)h(for)f(the)h(partitioning)f(suggest) g(themselv)o(es:)415 2598 y Fx(\017)41 b FG(In)18 b(problems)e(with)i (multiple)f(physical)f(v)n(ariables)h(per)g(node,)g(blocks)g(can)h(be)g (formed)e(by)h(grouping)e(the)498 2698 y(equations)k(per)h(node.)415 2863 y Fx(\017)41 b FG(In)26 b(structured)g(matrices,)h(such)g(as)g (those)g(from)e(partial)h(dif)n(ferential)f(equations)h(on)g(re)o (gular)f(grids,)i(a)498 2963 y(partitioning)18 b(can)i(be)g(based)g(on) g(the)g(physical)f(domain.)24 b(Examples)19 b(are)h(a)h(partitioning)d (along)h(lines)i(in)498 3062 y(the)f(2D)h(case,)f(or)g(planes)g(in)g (the)g(3D)g(case.)26 b(This)20 b(will)h(be)f(discussed)g(further)f(in)h Fx(x)p FG(3.4.3.)415 3227 y Fx(\017)41 b FG(On)24 b(parallel)g (computers)f(it)h(is)i(natural)d(to)h(let)h(the)f(partitioning)e (coincide)h(with)h(the)h(di)n(vision)e(of)h(v)n(ari-)498 3327 y(ables)c(o)o(v)o(er)f(the)h(processors.)291 3564 y Fp(3.2.2)98 b(Discussion)291 3719 y FG(Jacobi)21 b(preconditioners)e (need)i(v)o(ery)g(little)h(storage,)g(e)n(v)o(en)e(in)i(the)g(block)f (case,)i(and)e(the)o(y)g(are)h(easy)g(to)g(imple-)291 3819 y(ment.)i(Additionally)-5 b(,)18 b(on)i(parallel)f(computers)g (the)o(y)h(don')o(t)e(present)i(an)o(y)f(particular)g(problems.)415 3919 y(On)h(the)h(other)e(hand,)g(more)g(sophisticated)g (preconditioners)f(usually)h(yield)h(a)h(lar)o(ger)e(impro)o(v)o (ement.)3420 3888 y Fr(1)291 4198 y Fs(3.3)119 b(SSOR)31 b(pr)n(econditioning)291 4384 y FG(The)21 b(SSOR)i(preconditioner)1160 4354 y Fr(2)1212 4384 y FG(lik)o(e)f(the)f(Jacobi)h(preconditioner)m(,) c(can)k(be)f(deri)n(v)o(ed)f(from)h(the)h(coef)n(\002cient)e(ma-)291 4483 y(trix)g(without)f(an)o(y)h(w)o(ork.)415 4583 y(If)g(the)g (original,)f(symmetric,)g(matrix)h(is)h(decomposed)d(as)498 4746 y FC(A)23 b Fy(=)g FC(D)e Fy(+)d FC(L)g Fy(+)g FC(L)1059 4712 y FB(T)p 291 4805 1306 4 v 381 4861 a FI(1)410 4884 y FJ(Under)23 b(certain)i(conditions,)h(one)e(can)f(sho)n(w)g(that)h 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b(In)19 b(this)f(case)i(no)e(polynomial)j (acceleration)h(is)d(possible,)g Fi(i.e)o(.)p FJ(,)f(the)h (accelerating)k(polynomial)e(reduces)f(to)e(the)291 5439 y(tri)n(vial)j(polynomial)f Fk(P)831 5447 y Fh(n)874 5439 y Fl(\()p Fk(x)p Fl(\))j(=)f Fk(x)1108 5415 y Fh(n)1150 5439 y FJ(,)c(and)h(the)h(resulting)g(method)g(is)e(simply)h(the)g (stationary)i(SOR)e(method.)26 b(Recent)20 b(research)g(by)f(Eier)o(-) 291 5517 y(mann)h(and)h(V)-7 b(ar)o(ga)20 b([83])g(has)h(sho)n(wn)f (that)i(polynomial)g(acceleration)j(of)20 b(SOR)g(with)h(suboptimal)h Fk(!)g FJ(will)f(yield)h(no)e(impro)o(v)o(ement)i(o)o(v)o(er)291 5596 y(simple)17 b(SOR)g(with)h(optimal)g Fk(!)r FJ(.)p eop end %%Page: 38 48 TeXDict begin 38 47 bop 739 282 a FG(38)1905 b Fu(CHAPTER)21 b(3.)46 b(PRECONDITIONERS)739 515 y FG(in)20 b(its)h(diagonal,)e(lo)n (wer)m(,)g(and)h(upper)e(triangular)h(part,)h(the)g(SSOR)h(matrix)f(is) h(de\002ned)e(as)946 684 y FC(M)32 b Fy(=)23 b(\()p FC(D)e Fy(+)d FC(L)p Fy(\))p FC(D)1512 650 y FA(\000)p 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(depends)i(on)h(ho)n(w)f(well)i FC(M)2698 2990 y FA(\000)p Fz(1)2807 3021 y FG(approximates)e FC(A)3338 2990 y FA(\000)p Fz(1)3427 3021 y FG(.)739 3262 y Fp(3.4.1)99 b(Cr)n(eating)25 b(an)g(incomplete)h(factorization)739 3419 y FG(Incomplete)21 b(f)o(actorizations)g(are)i(the)f(\002rst)i(preconditioners)c(we)j(ha)n (v)o(e)f(encountered)e(so)j(f)o(ar)f(for)h(which)f(there)739 3518 y(is)k(a)g(non-tri)n(vial)d(creation)h(stage.)41 b(Incomplete)23 b(f)o(actorizations)h(may)h(break)f(do)n(wn)g (\(attempted)g(di)n(vision)h(by)739 3618 y(zero)18 b(pi)n(v)n(ot\))f (or)h(result)g(in)g(inde\002nite)g(matrices)g(\(ne)o(gati)n(v)o(e)e(pi) n(v)n(ots\))h(e)n(v)o(en)h(if)g(the)g(full)g(f)o(actorization)f(of)h (the)g(same)739 3718 y(matrix)h(is)j(guaranteed)c(to)i(e)o(xist)g(and)g (yield)g(a)g(positi)n(v)o(e)g(de\002nite)f(matrix.)863 3818 y(An)j(incomplete)e(f)o(actorization)f(is)k(guaranteed)c(to)i(e)o (xist)h(for)e(man)o(y)g(f)o(actorization)g(strate)o(gies)h(if)h(the)f (orig-)739 3918 y(inal)g(matrix)g(is)h(an)f FC(M)9 b FG(-matrix.)27 b(This)22 b(w)o(as)g(originally)e(pro)o(v)o(ed)f(by)i (Meijerink)f(and)h(V)-9 b(an)21 b(der)g(V)-11 b(orst)21 b([151)n(];)i(see)739 4017 y(further)c(Beauwens)h(and)f(Quenon)g([33)n (],)i(Manteuf)n(fel)d([146)n(],)i(and)g(V)-9 b(an)20 b(der)g(V)-11 b(orst)20 b([198)n(].)863 4117 y(In)d(cases)h(where)f(pi) n(v)n(ots)g(are)g(zero)g(or)f(ne)o(gati)n(v)o(e,)g(strate)o(gies)h(ha)n (v)o(e)g(been)f(proposed)f(such)i(as)h(substituting)e(an)739 4217 y(arbitrary)k(positi)n(v)o(e)h(number)f(\(see)i(K)n(ersha)o(w)f ([131)n(]\),)g(or)h(restarting)f(the)g(f)o(actorization)f(on)i FC(A)e Fy(+)f FC(\013I)29 b FG(for)21 b(some)739 4317 y(positi)n(v)o(e)e(v)n(alue)h(of)g FC(\013)h FG(\(see)f(Manteuf)n(fel)f ([146)n(]\).)863 4417 y(An)k(important)e(consideration)f(for)i (incomplete)f(f)o(actorization)g(preconditioners)e(is)24 b(the)e(cost)h(of)f(the)g(f)o(ac-)739 4517 y(torization)16 b(process.)23 b(Ev)o(en)16 b(if)i(the)f(incomplete)f(f)o(actorization)f (e)o(xists,)j(the)f(number)f(of)g(operations)g(in)m(v)n(olv)o(ed)f(in) 739 4616 y(creating)i(it)i(is)g(at)g(least)g(as)g(much)e(as)i(for)e (solving)h(a)g(system)h(with)f(such)g(a)h(coef)n(\002cient)e(matrix,)g (so)i(the)f(cost)h(may)739 4716 y(equal)i(that)h(of)f(one)g(or)g(more)g (iterations)g(of)h(the)f(iterati)n(v)o(e)g(method.)28 b(On)22 b(parallel)f(computers)f(this)i(problem)e(is)739 4816 y(aggra)n(v)n(ated)e(by)i(the)g(generally)f(poor)g(parallel)g(ef)n (\002cienc)o(y)g(of)h(the)g(f)o(actorization.)863 4916 y(Such)f(f)o(actorization)e(costs)i(can)f(be)h(amortized)e(if)i(the)f (iterati)n(v)o(e)g(method)f(tak)o(es)i(man)o(y)f(iterations,)g(or)g(if) h(the)739 5015 y(same)25 b(preconditioner)c(will)k(be)g(used)f(for)g (se)n(v)o(eral)g(linear)g(systems,)i(for)e(instance)g(in)h(successi)n (v)o(e)f(time)h(steps)739 5115 y(or)20 b(Ne)n(wton)f(iterations.)739 5340 y Fv(Solving)h(a)g(system)g(with)h(an)f(incomplete)h (factorization)c(pr)o(econditioner)739 5497 y FG(Incomplete)k(f)o 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b(incomplete)h(factorizations)291 4449 y FG(The)21 b(most)h(common)d(type)j(of)f(incomplete)f(f)o (actorization)g(is)j(based)e(on)g(taking)g(a)h(set)g FC(S)27 b FG(of)22 b(matrix)f(positions,)291 4549 y(and)31 b(k)o(eeping)f(all)j(positions)e(outside)g(this)h(set)h(equal)e(to)h (zero)f(during)f(the)i(f)o(actorization.)58 b(The)32 b(resulting)291 4648 y(f)o(actorization)18 b(is)j(incomplete)e(in)h (the)g(sense)h(that)f(\002ll)h(is)h(supressed.)415 4748 y(The)c(set)h FC(S)24 b FG(is)19 b(usually)f(chosen)f(to)h(encompass)g (all)g(positions)g Fy(\()p FC(i;)c(j)5 b Fy(\))19 b FG(for)f(which)f FC(a)2787 4760 y FB(i;j)2889 4748 y Fx(6)p Fy(=)22 b(0)p FG(.)j(A)18 b(position)g(that)291 4848 y(is)24 b(zero)f(in)g FC(A)h FG(b)n(ut)g(not)f(so)h(in)f(an)g(e)o(xact)g(f)o(actorization) 1877 4817 y Fr(3)1932 4848 y FG(is)h(called)g(a)f Ft(\002ll)h FG(position,)f(and)g(if)h(it)g(is)g(outside)f FC(S)5 b FG(,)24 b(the)291 4947 y(\002ll)d(there)f(is)h(said)g(to)g(be)f (\223discarded\224.)25 b(Often,)20 b 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b(called)e FC(D)r FG(-)p FC(I)7 b(LU)38 b FG(\(Pom-)739 4658 y(merell)24 b([173)n(]\),)h(e)n(v)o (en)e(less)i(is)g(needed.)35 b(If)24 b(not)g(only)f(we)i(prohibit)d (\002ll-in)i(elements,)h(b)n(ut)f(we)g(also)h(alter)f(only)739 4757 y(the)f(diagonal)e(elements)h(\(that)g(is,)i(an)o(y)e(alterations) g(of)h(of)n(f-diagonal)c(elements)k(are)f(ignored)3500 4727 y Fr(5)3531 4757 y FG(\),)h(we)g(ha)n(v)o(e)f(the)739 4857 y(follo)n(wing)c(situation.)863 4958 y(Splitting)j(the)g(coef)n (\002cient)f(matrix)h(into)f(its)j(diagonal,)c(lo)n(wer)i(triangular)m (,)e(and)h(upper)g(triangular)f(parts)j(as)739 5058 y FC(A)h Fy(=)g FC(D)981 5070 y FB(A)1039 5058 y Fy(+)t FC(L)1165 5070 y FB(A)1222 5058 y Fy(+)t FC(U)1348 5070 y FB(A)1401 5058 y FG(,)17 b(the)g(preconditioner)c(can)j(be)g(written) g(as)h FC(M)32 b Fy(=)22 b(\()p FC(D)6 b Fy(+)t FC(L)3057 5070 y FB(A)3111 5058 y Fy(\))p FC(D)3214 5028 y FA(\000)p Fz(1)3303 5058 y Fy(\()p FC(D)g Fy(+)t FC(U)3536 5070 y FB(A)3590 5058 y Fy(\))17 b 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b(the)f(\002ll)i(is)g(multiplied)d(by) h(a)h(parameter)f Fy(0)29 b FC(<)g(\013)g(<)h Fy(1)23 b FG(before)f(it)j(is)f(subtracted)739 3209 y(from)29 b(the)h(diagonal;)j(see)e(Ashcraft)e(and)h(Grimes)g([11)o(],)i(Ax)o (elsson)d(and)h(Lindsk)o(og)e([18)o(,)i(19)o(],)j(Chan)d([44)n(],)739 3309 y(Eijkhout)19 b([85)o(],)i(Notay)g([161)n(],)g(Stone)g([193)n(],)g (and)g(V)-9 b(an)20 b(der)h(V)-11 b(orst)21 b([202)o(].)27 b(F)o(or)21 b(the)g(dangers)f(of)g(MILU)h(in)g(the)739 3408 y(presence)e(of)h(rounding)e(error)m(,)g(see)j(V)-9 b(an)20 b(der)f(V)-11 b(orst)21 b([204)n(].)739 3629 y Fv(V)-8 b(ectorization)18 b(of)i(the)g(pr)o(econditioner)f(solv)o(e) 739 3784 y FG(At)f(\002rst)f(it)h(may)f(appear)f(that)h(the)g (sequential)f(time)i(of)e(solving)g(a)i(f)o(actorization)d(is)j(of)f (the)g(order)f(of)h(the)g(number)739 3884 y(of)k(v)n(ariables,)f(b)n (ut)h(things)f(are)h(not)g(quite)f(that)h(bad.)27 b(Consider)20 b(the)h(special)g(case)h(of)f(central)f(dif)n(ferences)f(on)i(a)739 3984 y(re)o(gular)f(domain)h(of)g FC(n)f Fx(\002)f FC(n)j FG(points.)30 b(The)21 b(v)n(ariables)g(on)h(an)o(y)f(diagonal)f(in)i (the)g(domain,)f(that)h(is,)h(in)f(locations)739 4083 y Fy(\()p FC(i;)14 b(j)5 b Fy(\))23 b FG(with)f FC(i)d Fy(+)h FC(j)31 b Fy(=)c FC(k)s FG(,)22 b(depend)f(only)g(on)h(those)g (on)f(the)h(pre)n(vious)f(diagonal,)g(that)h(is,)h(with)g FC(i)c Fy(+)h FC(j)31 b Fy(=)26 b FC(k)d Fx(\000)c Fy(1)p FG(.)739 4183 y(Therefore)d(it)i(is)h(possible)f(to)g(process)f(the)h (operations)f(on)g(such)h(a)g(diagonal,)f(or)h(`w)o(a)n(v)o(efront',)d (in)k(parallel)e(\(see)739 4282 y(\002gure)i(3.4\),)g(or)h(ha)n(v)o(e)g (a)g(v)o(ector)f(computer)g Ft(pipeline)g FG(them;)h(see)h(V)-9 b(an)19 b(der)h(V)-11 b(orst)21 b([201)n(,)f(203)o(].)863 4382 y(Another)g(w)o(ay)g(of)h(v)o(ectorizing)d(the)j(solution)e(of)i (the)f(triangular)f(f)o(actors)i(is)g(to)g(use)g(some)f(form)g(of)g(e)o (xpan-)739 4482 y(sion)25 b(of)g(the)h(in)m(v)o(erses)e(of)h(the)h(f)o (actors.)40 b(Consider)25 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FG(If)i(the)h(physical)e (problem)g(has)h(se)n(v)o(eral)g(v)n(ariables)g(per)g(grid)g(point,)h (that)g(is,)i(if)e(there)f(are)g(se)n(v)o(eral)g(coupled)739 2001 y(partial)20 b(dif)n(ferential)e(equations,)h(it)i(is)g(possible)f (to)g(introduce)f(blocking)f(in)i(a)h(natural)e(w)o(ay)-5 b(.)863 2101 y(Blocking)31 b(of)h(the)f(equations)g(\(which)g(gi)n(v)o (es)g(a)h(small)g(number)e(of)i(v)o(ery)e(lar)o(ge)h(blocks\))g(w)o(as) h(used)g(by)739 2200 y(Ax)o(elsson)24 b(and)h(Gustafsson)f([17)o(])h (for)g(the)g(equations)e(of)i(linear)g(elasticity)-5 b(,)26 b(and)e(blocking)f(of)i(the)g(v)n(ariables)739 2300 y(per)31 b(node)g(\(which)h(gi)n(v)o(es)f(man)o(y)g(v)o(ery)g (small)h(blocks\))f(w)o(as)i(used)f(by)f(Aarden)g(and)h(Karlsson)f([1]) h(for)f(the)739 2400 y(semiconductor)21 b(equations.)33 b(A)23 b(systematic)h(comparison)d(of)i(the)g(tw)o(o)h(approaches)d(w)o (as)j(made)f(by)g(Bank,)h Ft(et)739 2499 y(al.)c FG([26)o(].)739 2733 y Fp(3.4.5)99 b(Incomplete)26 b(LQ)e(factorizations)739 2889 y FG(Saad)g([183)n(])g(proposes)f(to)h(construct)f(an)h (incomplete)e(LQ)j(f)o(actorization)d(of)i(a)g(general)f(sparse)h (matrix.)36 b(The)739 2989 y(idea)29 b(is)g(to)g(orthogonalize)d(the)j (ro)n(ws)g(of)f(the)h(matrix)f(by)h(a)g(Gram-Schmidt)e(process)h (\(note)g(that)h(in)g(sparse)739 3088 y(matrices,)18 b(most)f(ro)n(ws)h(are)f(typically)g(orthogonal)d(already)-5 b(,)17 b(so)h(that)f(standard)g(Gram-Schmidt)e(may)i(be)h(not)f(so)739 3188 y(bad)f(as)i(in)f(general\).)22 b(Saad)17 b(suggest)f(dropping)e (strate)o(gies)j(for)f(the)h(\002ll-in)g(produced)d(in)j(the)g (orthogonalization)739 3287 y(process.)23 b(It)16 b(turns)g(out)g(that) g(the)g(resulting)g(incomplete)e(L)j(f)o(actor)e(can)h(be)g(vie)n(wed)g (as)h(the)f(incomplete)e(Choleski)739 3387 y(f)o(actor)h(of)h(the)g (matrix)g FC(AA)1510 3357 y FB(T)1562 3387 y FG(.)25 b(Experiments)14 b(sho)n(w)i(that)g(using)f FC(L)i FG(in)f(a)g(CG)h (process)f(for)f(the)i(normal)d(equations:)739 3487 y FC(L)796 3457 y FA(\000)p Fz(1)885 3487 y FC(AA)1009 3457 y FB(T)1061 3487 y FC(L)1118 3457 y FA(\000)p FB(T)1222 3487 y FC(y)26 b Fy(=)c FC(b)f FG(is)g(ef)n(fecti)n(v)o(e)e(for)g(some) h(rele)n(v)n(ant)f(problems.)739 3763 y Fs(3.5)119 b(P)n(olynomial)29 b(pr)n(econditioners)739 3949 y FG(So)c(f)o(ar)m(,)g(we)f(ha)n(v)o(e)g (described)f(preconditioners)f(in)j(only)e(one)h(of)g(tw)o(o)h (classes:)35 b(those)25 b(that)f(approximate)e(the)739 4048 y(coef)n(\002cient)17 b(matrix,)g(and)g(where)h(linear)f(systems)h (with)g(the)g(preconditioner)d(as)j(coef)n(\002cient)f(matrix)g(are)h (easier)739 4148 y(to)h(solv)o(e)g(than)f(the)h(original)f(system.)25 b Ft(P)-7 b(olynomial)18 b FG(preconditioners)e(can)j(be)g(considered)e (as)j(members)d(of)i(the)739 4248 y(second)g(class)i(of)f (preconditioners:)j(direct)c(approximations)f(of)i(the)g(in)m(v)o(erse) f(of)h(the)g(coef)n(\002cient)f(matrix.)863 4347 y(Suppose)e(that)g (the)h(coef)n(\002cient)e(matrix)h FC(A)i FG(of)e(the)g(linear)h 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b(the)i(best)h(polynomial)d(that)i(minimizes)g Fx(k)p FC(I)i Fx(\000)15 b FC(M)2062 1190 y FA(\000)p Fz(1)2150 1221 y FC(A)p Fx(k)p FG(.)25 b(F)o(or)19 b(the)g(choice)g(of) g(the)g(in\002nity)g(norm)f(we)291 1320 y(thus)24 b(obtain)g(Chebyshe)n (v)f(polynomials,)h(and)g(the)o(y)g(require)g(estimates)h(of)g(both)f (a)h(lo)n(wer)f(and)g(upper)g(bound)291 1420 y(on)c(the)h(spectrum)e (of)h FC(A)p FG(.)28 b(These)20 b(estimates)h(may)g(be)f(deri)n(v)o(ed) f(from)h(the)g(conjugate)f(gradient)g(iteration)h(itself;)291 1519 y(see)g Fx(x)p FG(5.1.)415 1623 y(Since)f(an)g(accurate)f(lo)n (wer)g(bound)f(on)i(the)f(spectrum)g(of)h FC(A)g FG(may)g(be)g(hard)f (to)h(obtain,)f(Johnson,)f(Micchelli)291 1723 y(and)d(P)o(aul)h([125)o (])g(and)g(Saad)g([182)n(])h(propose)d(least)j(squares)f(polynomials)e (based)i(on)g(se)n(v)o(eral)g(weight)g(functions.)291 1822 y(These)26 b(functions)f(only)h(require)g(an)g(upper)g(bound)e (and)i(this)i(is)f(easily)g(computed,)f(using)h(for)f(instance)g(the) 291 1922 y(\223Gerschgorin)h(bound\224)g Fy(max)1197 1934 y FB(i)1238 1860 y Fw(P)1326 1947 y FB(j)1375 1922 y Fx(j)p FC(A)1460 1934 y FB(i;j)1538 1922 y Fx(j)p FG(;)35 b(see)30 b([209)n(,)i Fx(x)p FG(1.4].)51 b(Experiments)28 b(comparing)f(Chebyshe)n(v)g(and)291 2021 y(least)21 b(squares)e(polynomials)g(can)h(be)g(found)e(in)i(Ashby)-5 b(,)19 b(Manteuf)n(fel)g(and)h(Otto)g([8)o(].)415 2125 y(Application)26 b(of)h(polynomial)e(preconditioning)f(to)j(symmetric)g (inde\002nite)f(problems)g(is)i(described)e(by)291 2225 y(Ashby)-5 b(,)19 b(Manteuf)n(fel)f(and)i(Saylor)g([9)o(].)25 b(There)20 b(the)g(polynomial)e(is)k(chosen)d(so)i(that)f(it)h (transforms)e(the)i(system)291 2324 y(into)f(a)g(de\002nite)g(one.)291 2626 y Fs(3.6)119 b(Pr)n(econditioners)24 b(fr)n(om)e(pr)n(operties)i (of)f(the)h(differ)n(ential)g(equation)291 2819 y FG(A)f(number)f(of)h (preconditioners)e(e)o(xist)i(that)h(deri)n(v)o(e)e(their)h (justi\002cation)g(from)f(properties)g(of)h(the)h(underlying)291 2919 y(partial)k(dif)n(ferential)g(equation.)50 b(W)-7 b(e)30 b(will)f(co)o(v)o(er)f(some)h(of)f(them)h(here)g(\(see)g(also)g Fx(x)p FG(5.5)f(and)h Fx(x)p FG(5.4\).)50 b(These)291 3018 y(preconditioners)15 b(usually)j(in)m(v)n(olv)o(e)f(more)h(w)o (ork)g(than)g(the)h(types)f(discussed)h(abo)o(v)o(e,)e(ho)n(we)n(v)o (er)m(,)f(the)o(y)i(allo)n(w)h(for)291 3118 y(specialized)g(f)o(aster)i (solution)e(methods.)291 3377 y Fp(3.6.1)98 b(Pr)n(econditioning)26 b(by)g(the)f(symmetric)g(part)291 3540 y FG(In)g Fx(x)p FG(2.3.4)f(we)i(pointed)e(out)h(that)h(conjugate)e(gradient)g(methods)h (for)f(non-self)o(adjoint)g(systems)i(require)e(the)291 3640 y(storage)18 b(of)h(pre)n(viously)e(calculated)h(v)o(ectors.)24 b(Therefore)17 b(it)j(is)g(some)n(what)e(remarkable)f(that)j (preconditioning)291 3739 y(by)e(the)g(symmetric)g(part)g Fy(\()p FC(A)13 b Fy(+)g FC(A)1278 3709 y FB(T)1330 3739 y Fy(\))p FC(=)p Fy(2)19 b FG(of)f(the)h(coef)n(\002cient)e(matrix)h FC(A)h FG(leads)g(to)g(a)g(method)e(that)i(does)f(not)h(need)291 3839 y(this)g(e)o(xtended)d(storage.)24 b(Such)18 b(a)h(method)f(w)o (as)h(proposed)e(by)h(Concus)g(and)g(Golub)g([55)n(])h(and)f(W)m (idlund)g([214)n(].)415 3942 y(Ho)n(we)n(v)o(er)m(,)j(solving)h(a)h (system)g(with)g(the)g(symmetric)f(part)g(of)g(a)h(matrix)g(may)f(be)g (no)h(easier)g(than)f(solving)291 4042 y(a)e(system)f(with)h(the)g (full)f(matrix.)24 b(This)c(problem)e(may)h(be)h(tackled)f(by)g (imposing)f(a)i(nested)g(iterati)n(v)o(e)f(method,)291 4142 y(where)29 b(a)h(preconditioner)d(based)j(on)f(the)h(symmetric)f (part)h(is)h(used.)54 b(V)-9 b(assile)n(vski)30 b([210)n(])g(pro)o(v)o (ed)e(that)i(the)291 4241 y(ef)n(\002cienc)o(y)18 b(of)i(this)h (preconditioner)c(for)i(the)i(symmetric)e(part)h(carries)g(o)o(v)o(er)f (to)h(the)g(outer)g(method.)291 4501 y Fp(3.6.2)98 b(The)26 b(use)g(of)f(fast)f(solv)o(ers)291 4664 y FG(In)c(man)o(y)g (applications,)f(the)i(coef)n(\002cient)e(matrix)h(is)i(symmetric)e (and)g(positi)n(v)o(e)g(de\002nite.)26 b(The)20 b(reason)g(for)g(this) 291 4763 y(is)30 b(usually)f(that)g(the)h(partial)f(dif)n(ferential)e (operator)h(from)g(which)h(it)h(is)h(deri)n(v)o(ed)c(is)k (self-adjoint,)f(coerci)n(v)o(e,)291 4863 y(and)21 b(bounded)f(\(see)i (Ax)o(elsson)g(and)f(Bark)o(er)h([14)o(,)h Fx(x)p FG(3.2]\).)29 b(It)23 b(follo)n(ws)e(that)i(for)e(the)h(coef)n(\002cient)f(matrix)h FC(A)h FG(the)291 4963 y(follo)n(wing)18 b(relation)i(holds)f(for)h(an) o(y)f(matrix)h FC(B)25 b FG(from)19 b(a)h(similar)h(dif)n(ferential)d (equation:)498 5197 y FC(c)534 5209 y Fz(1)594 5197 y Fx(\024)694 5141 y FC(x)741 5111 y FB(T)794 5141 y FC(Ax)p 692 5178 215 4 v 692 5254 a(x)739 5230 y FB(T)792 5254 y FC(B)t(x)939 5197 y Fx(\024)23 b FC(c)1063 5209 y Fz(2)1183 5197 y FG(for)d(all)g FC(x)q(;)291 5397 y FG(where)25 b FC(c)556 5409 y Fz(1)594 5397 y FG(,)j FC(c)679 5409 y Fz(2)743 5397 y FG(do)e(not)g(depend)f(on)h(the)h(matrix)e(size.)45 b(The)26 b(importance)f(of)h(this)h(is)g(that)g(the)f(use)h(of)f FC(B)31 b FG(as)c(a)291 5497 y(preconditioner)22 b(gi)n(v)o(es)i(an)h (iterati)n(v)o(e)g(method)f(with)h(a)h(number)d(of)i(iterations)g(that) h(does)f(not)f(depend)g(on)h(the)291 5596 y(matrix)19 b(size.)p eop end %%Page: 48 58 TeXDict begin 48 57 bop 739 282 a FG(48)1905 b Fu(CHAPTER)21 b(3.)46 b(PRECONDITIONERS)863 515 y FG(Thus)16 b(we)g(can)g (precondition)e(our)h(original)g(matrix)g(by)h(one)f(deri)n(v)o(ed)g (from)g(a)h(dif)n(ferent)e(PDE,)j(if)f(one)f(can)h(be)739 615 y(found)i(that)j(has)f(attracti)n(v)o(e)g(properties)f(as)i (preconditioner)-5 b(.)22 b(The)e(most)g(common)f(choice)g(is)i(to)g (tak)o(e)f(a)h(matrix)739 715 y(from)28 b(a)i Ft(separ)o(able)f FG(PDE.)h(A)g(system)f(in)m(v)n(olving)f(such)h(a)h(matrix)f(can)h(be)f (solv)o(ed)g(with)g(v)n(arious)g(so-called)739 814 y(\223f)o(ast)22 b(solv)o(ers\224,)g(such)g(as)g(FFT)h(methods,)e(c)o(yclic)g (reduction,)g(or)g(the)h(generalized)f(marching)f(algorithm)g(\(see)739 914 y(Dorr)f([74)o(],)h(Sw)o(arztrauber)f([194)n(],)h(Bank)g([25)o(])g (and)g(Bank)g(and)f(Rose)i([27)o(]\).)863 1014 y(As)k(a)e(simplest)h(e) o(xample,)f(an)o(y)f(elliptic)i(operator)e(can)h(be)g(preconditioned)d (with)k(the)f(Poisson)h(operator)m(,)739 1114 y(gi)n(ving)19 b(the)h(iterati)n(v)o(e)f(method)946 1282 y Fx(\000)p Fy(\001\()p FC(u)1160 1294 y FB(n)p Fz(+1)1308 1282 y Fx(\000)f FC(u)1439 1294 y FB(n)1483 1282 y Fy(\))24 b(=)e Fx(\000)p Fy(\()p Fx(L)p FC(u)1828 1294 y FB(n)1892 1282 y Fx(\000)c FC(f)9 b Fy(\))p FC(:)739 1450 y FG(In)25 b(Concus)g(and)g(Golub)f([58)o(])h(a)h(transformation)d(of)i(this)h (method)e(is)i(considered)e(to)h(speed)g(up)g(the)g(con)m(v)o(er)n(-) 739 1549 y(gence.)f(As)d(another)e(e)o(xample,)f(if)j(the)f(original)f (matrix)h(arises)g(from)946 1718 y Fx(\000)p Fy(\()p FC(a)p Fy(\()p FC(x;)14 b(y)s Fy(\))p FC(u)1327 1730 y FB(x)1369 1718 y Fy(\))1401 1730 y FB(x)1462 1718 y Fx(\000)k Fy(\()p FC(b)p Fy(\()p FC(x;)c(y)s Fy(\))p FC(u)1853 1730 y FB(y)1893 1718 y Fy(\))1925 1730 y FB(y)1988 1718 y Fy(=)23 b FC(f)t(;)739 1885 y FG(the)d(preconditioner)d(can)j (be)g(formed)f(from)946 2054 y Fx(\000)p Fy(\()q(~)-43 b FC(a)p Fy(\()p FC(x)p Fy(\))p FC(u)1246 2066 y FB(x)1289 2054 y Fy(\))1321 2066 y FB(x)1381 2054 y Fx(\000)18 b Fy(\()1493 2032 y(~)1496 2054 y FC(b)p Fy(\()p FC(y)s Fy(\))p FC(u)1688 2066 y FB(y)1728 2054 y Fy(\))1760 2066 y FB(y)1823 2054 y Fy(=)23 b FC(f)t(:)739 2221 y FG(An)d(e)o(xtension)f(to)h(the)g(non-self)f(adjoint)h(case)g(is)h (considered)e(by)h(Elman)f(and)h(Schultz)g([93)n(].)863 2322 y(F)o(ast)h(solv)o(ers)f(are)g(attracti)n(v)o(e)f(in)h(that)g(the) g(number)f(of)g(operations)g(the)o(y)g(require)g(is)i(\(slightly)e (higher)g(than\))739 2421 y(of)j(the)h(order)e(of)i(the)f(number)f(of)h (v)n(ariables.)32 b(Coupled)21 b(with)i(the)g(f)o(act)g(that)f(the)h (number)e(of)h(iterations)g(in)h(the)739 2521 y(resulting)15 b(preconditioned)e(iterati)n(v)o(e)j(methods)f(is)i(independent)d(of)i (the)g(matrix)g(size,)i(such)e(methods)f(are)h(close)739 2620 y(to)22 b(optimal.)30 b(Ho)n(we)n(v)o(er)m(,)21 b(f)o(ast)i(solv)o(ers)e(are)h(usually)g(only)f(applicable)g(if)i(the)f (physical)f(domain)g(is)i(a)f(rectangle)739 2720 y(or)e(other)g (Cartesian)g(product)f(structure.)25 b(\(F)o(or)20 b(a)h(domain)e (consisting)h(of)g(a)h(number)e(of)h(such)g(pieces,)h(domain)739 2820 y(decomposition)d(methods)h(can)h(be)g(used;)g(see)h Fx(x)p FG(5.4\).)739 3060 y Fp(3.6.3)99 b(Alter)o(nating)25 b(Dir)n(ection)g(Implicit)g(methods)739 3217 y FG(The)20 b(Poisson)g(dif)n(ferential)e(operator)h(can)h(be)g(split)h(in)f(a)h (natural)e(w)o(ay)h(as)h(the)f(sum)g(of)g(tw)o(o)h(operators:)946 3397 y Fx(L)j Fy(=)e Fx(L)1171 3409 y Fz(1)1227 3397 y Fy(+)c Fx(L)1367 3409 y Fz(2)1405 3397 y FC(;)180 b FG(where)19 b Fx(L)1888 3409 y Fz(1)1949 3397 y Fy(=)k Fx(\000)2130 3364 y FB(@)2169 3339 y Fo(2)p 2111 3378 110 4 v 2111 3425 a FB(@)t(x)2188 3409 y Fo(2)2230 3397 y FG(,)e Fx(L)2329 3409 y Fz(2)2389 3397 y Fy(=)i Fx(\000)2569 3364 y FB(@)2608 3339 y Fo(2)p 2551 3378 108 4 v 2551 3425 a FB(@)t(y)2626 3409 y Fo(2)2669 3397 y FC(:)739 3564 y FG(No)n(w)c(let)h FC(L)1078 3576 y Fz(1)1115 3564 y FG(,)g FC(L)1213 3576 y Fz(2)1269 3564 y FG(be)g(discretized)e (representations)g(of)h Fx(L)2416 3576 y Fz(1)2453 3564 y FG(,)h Fx(L)2551 3576 y Fz(2)2588 3564 y FG(.)26 b(Based)19 b(on)g(the)h(observ)n(ation)d(that)i FC(L)3688 3576 y Fz(1)3740 3564 y Fy(+)c FC(L)3877 3576 y Fz(2)3937 3564 y Fy(=)739 3664 y(\()p FC(I)26 b Fy(+)18 b FC(L)973 3676 y Fz(1)1009 3664 y Fy(\)\()p FC(I)26 b Fy(+)18 b FC(L)1275 3676 y Fz(2)1312 3664 y Fy(\))h Fx(\000)f FC(I)25 b Fx(\000)18 b FC(L)1647 3676 y Fz(1)1684 3664 y FC(L)1741 3676 y Fz(2)1778 3664 y FG(,)i(iterati)n(v)o(e)g(schemes)g(such)g(as)946 3832 y Fy(\(1)f(+)f FC(\013L)1232 3844 y Fz(1)1269 3832 y Fy(\)\(1)g(+)g FC(\013L)1586 3844 y Fz(2)1624 3832 y Fy(\))p FC(u)1704 3798 y Fz(\()p FB(m)p Fz(+1\))1925 3832 y Fy(=)23 b([\(1)18 b(+)g FC(\014)t(L)2319 3844 y Fz(1)2357 3832 y Fy(\)\(1)g(+)g FC(\014)t(L)2672 3844 y Fz(2)2709 3832 y Fy(\)])c FC(u)2826 3798 y Fz(\()p FB(m)p Fz(\))739 4000 y FG(with)20 b(suitable)g(choices)g(of)g FC(\013)h FG(and)f FC(\014)25 b FG(ha)n(v)o(e)19 b(been)h(proposed.)863 4100 y(This)30 b Ft(alternating)e(dir)m(ection)g(implicit)p FG(,)j(or)e Ft(ADI)p FG(,)g(method)f(w)o(as)i(\002rst)g(proposed)d(as)j (a)f(solution)g(method)739 4200 y(for)d(parabolic)f(equations.)43 b(The)27 b FC(u)1788 4170 y Fz(\()p FB(m)p Fz(\))1929 4200 y FG(are)g(then)f(approximations)e(on)i(subsequent)f(time)i (steps.)45 b(Ho)n(we)n(v)o(er)m(,)739 4299 y(it)31 b(can)f(also)g(be)g (used)g(for)f(the)h(steady)g(state,)j(that)d(is,)j(for)d(solving)f (elliptic)h(equations.)54 b(In)29 b(that)h(case,)j(the)739 4399 y FC(u)787 4369 y Fz(\()p FB(m)p Fz(\))930 4399 y FG(become)26 b(subsequent)g(iterates;)32 b(see)d(D'Y)-8 b(ak)o(ono)o(v)24 b([81)o(],)30 b(F)o(airweather)m(,)d(Gourlay)g(and)g (Mitchell)h([96)n(],)739 4499 y(Hadjidimos)d([118)n(],)i(and)e (Peaceman)g(and)g(Rachford)f([172)n(].)42 b(Generalization)24 b(of)h(this)h(scheme)g(to)f(v)n(ariable)739 4598 y(coef)n(\002cients)19 b(or)h(fourth)f(order)g(elliptic)h(problems)f(is)i(relati)n(v)o(ely)e (straightforw)o(ard.)863 4698 y(The)24 b(abo)o(v)o(e)d(method)i(is)h (implicit)g(since)f(it)h(requires)f(systems)h(solutions,)g(and)e(it)j (alternates)e(the)g FC(x)i FG(and)e FC(y)739 4798 y FG(\(and)g(if)h (necessary)f FC(z)t FG(\))g(directions.)35 b(It)24 b(is)h(attracti)n(v) o(e)d(from)h(a)h(practical)g(point)f(of)g(vie)n(w)h(\(although)d (mostly)j(on)739 4898 y(tensor)h(product)f(grids\),)i(since)g(solving)e (a)i(system)g(with,)h(for)e(instance,)h(a)g(matrix)f FC(I)30 b Fy(+)22 b FC(\013L)3485 4910 y Fz(1)3548 4898 y FG(entails)k(only)f(a)739 4997 y(number)20 b(of)h(uncoupled)e (tridiagonal)h(solutions.)28 b(These)22 b(need)f(v)o(ery)f(little)i (storage)f(o)o(v)o(er)f(that)i(needed)e(for)h(the)739 5097 y(matrix,)e(and)h(the)o(y)f(can)h(be)g(e)o(x)o(ecuted)f(in)h (parallel,)g(or)f(one)h(can)g(v)o(ectorize)f(o)o(v)o(er)g(them.)863 5197 y(A)28 b(theoretical)d(reason)h(that)h(ADI)f(preconditioners)e (are)j(of)f(interest)h(is)g(that)g(the)o(y)f(can)g(be)h(sho)n(wn)f(to)g (be)739 5297 y(spectrally)21 b(equi)n(v)n(alent)f(to)j(the)f(original)e (coef)n(\002cient)h(matrix.)30 b(Hence)21 b(the)h(number)f(of)g (iterations)h(is)h(bounded)739 5396 y(independent)17 b(of)j(the)h(condition)d(number)-5 b(.)863 5497 y(Ho)n(we)n(v)o(er)m(,) 19 b(there)h(is)i(a)f(problem)e(of)h(data)h(distrib)n(ution.)k(F)o(or) 20 b(v)o(ector)g(computers,)f(either)h(the)h(system)g(solu-)739 5596 y(tion)c(with)i FC(L)1110 5608 y Fz(1)1165 5596 y FG(or)e(with)h FC(L)1475 5608 y Fz(2)1530 5596 y FG(will)h(in)m(v)n (olv)o(e)d(v)o(ery)h(lar)o(ge)g(strides:)24 b(if)18 b(columns)f(of)h(v) n(ariables)f(in)h(the)g(grid)f(are)h(stored)p eop end %%Page: 49 59 TeXDict begin 49 58 bop 291 282 a Fu(3.6.)45 b(O)m(THER)20 b(PRECONDITIONERS)1948 b FG(49)291 515 y(contiguously)-5 b(,)20 b(only)h(the)i(solution)f(with)h FC(L)1573 527 y Fz(1)1632 515 y FG(will)h(in)m(v)n(olv)o(e)d(contiguous)f(data.)32 b(F)o(or)22 b(the)h FC(L)2949 527 y Fz(2)3009 515 y FG(the)g(stride)f (equals)291 615 y(the)e(number)e(of)i(v)n(ariables)f(in)i(a)f(column.) 415 715 y(On)d(parallel)g(machines)g(an)g(ef)n(\002cient)f(solution)h (is)h(possible)f(if)h(the)f(processors)f(are)h(arranged)e(in)j(a)f FC(P)3338 727 y FB(x)3388 715 y Fx(\002)8 b FC(P)3514 727 y FB(y)291 814 y FG(grid.)53 b(During,)31 b(e.g.,)h(the)e FC(L)1152 826 y Fz(1)1219 814 y FG(solv)o(e,)i(e)n(v)o(ery)d(processor) g(ro)n(w)g(then)h(w)o(orks)f(independently)e(of)j(other)f(ro)n(ws.)291 914 y(Inside)18 b(each)h(ro)n(w)-5 b(,)19 b(the)g(processors)g(can)g(w) o(ork)g(together)m(,)e(for)i(instance)g(using)g(a)h(Schur)e(complement) g(method.)291 1013 y(W)m(ith)25 b(suf)n(\002cient)f(netw)o(ork)g (bandwidth)f(this)j(will)f(essentially)g(reduce)f(the)h(time)g(to)h (that)f(for)f(solving)g(an)o(y)g(of)291 1113 y(the)g(subdomain)e (systems)i(plus)g(the)h(time)f(for)f(the)i(interf)o(ace)e(system.)37 b(Thus,)24 b(this)h(method)e(will)h(be)g(close)h(to)291 1213 y(optimal.)p eop end %%Page: 50 60 TeXDict begin 50 59 bop 739 282 a FG(50)1905 b Fu(CHAPTER)21 b(3.)46 b(PRECONDITIONERS)p eop end %%Page: 51 61 TeXDict begin 51 60 bop 291 1139 a FD(Chapter)44 b(4)291 1555 y FF(Related)51 b(Issues)291 2037 y Fs(4.1)119 b(Complex)30 b(Systems)291 2225 y FG(Conjugate)19 b(gradient)g(methods)h(for)g(real) g(symmetric)g(systems)h(can)g(be)f(applied)g(to)h(comple)o(x)e (Hermitian)h(sys-)291 2324 y(tems)j(in)h(a)f(straightforw)o(ard)e (manner)-5 b(.)33 b(F)o(or)23 b(non-Hermitian)e(comple)o(x)g(systems)j (we)g(distinguish)e(tw)o(o)h(cases.)291 2424 y(In)k(general,)g(for)g (an)o(y)g(coef)n(\002cient)f(matrix)g(a)i(CGNE)g(method)e(is)i (possible,)h(that)e(is,)j(a)e(conjugate)d(gradients)291 2524 y(method)18 b(on)i(the)g(normal)f(equations)g FC(A)1443 2494 y FB(H)1506 2524 y FC(Ax)24 b Fy(=)f FC(A)1789 2494 y FB(H)1852 2524 y FC(b)p FG(,)d(or)g(one)g(can)g(split)g(the)h(system) f(into)g(real)g(and)g(comple)o(x)291 2623 y(parts)j(and)g(use)g(a)h (method)e(such)h(as)h(GMRES)g(on)f(the)g(resulting)g(real)g (nonsymmetric)e(system.)35 b(Ho)n(we)n(v)o(er)m(,)22 b(in)291 2723 y(certain)d(practical)h(situations)g(the)g(comple)o(x)f (system)h(is)h(non-Hermitian)d(b)n(ut)i(symmetric.)415 2824 y(Comple)o(x)38 b(symmetric)f(systems)j(can)e(be)h(solv)o(ed)e(by) i(a)g(classical)g(conjugate)e(gradient)g(or)i(Lanczos)291 2923 y(method,)22 b(that)h(is,)i(with)f(short)f(recurrences,)f(if)h (the)g(comple)o(x)f(inner)g(product)g Fy(\()p FC(x;)14 b(y)s Fy(\))29 b(=)34 b(\026)-47 b FC(x)2966 2893 y FB(T)3018 2923 y FC(y)27 b FG(is)d(replaced)e(by)291 3023 y Fy(\()p FC(x;)14 b(y)s Fy(\))32 b(=)g FC(x)659 2993 y FB(T)712 3023 y FC(y)s FG(.)40 b(Lik)o(e)25 b(the)g(BiConjugate)f(Gradient)h 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Fz(\()p FB(i)p Fz(\))1423 4063 y Fx(\021)k FC(x)1558 4033 y Fz(\()p FB(i)p Fz(\))1656 4063 y Fx(\000)18 b FC(x)k FG(is)f(small)f(enough)f(to)h(stop,)394 4233 y(2.)41 b(stop)20 b(if)h(the)f(error)f(is)i(no)f(longer)f(decreasing)g(or)g (decreasing)g(too)h(slo)n(wly)-5 b(,)20 b(and)394 4403 y(3.)41 b(limit)21 b(the)f(maximum)e(amount)h(of)h(time)h(spent)f (iterating.)415 4572 y(F)o(or)25 b(the)h(user)f(wishing)g(to)g(read)g (as)h(little)g(as)g(possible,)h(the)e(follo)n(wing)f(simple)h(stopping) f(criterion)g(will)291 4671 y(lik)o(ely)f(be)g(adequate.)34 b(The)23 b(user)g(must)h(supply)f(the)g(quantities)g FC(maxit)p FG(,)h Fx(k)p FC(b)p Fx(k)p FG(,)g Ft(stop)p 2753 4671 25 4 v 29 w(tol)p FG(,)g(and)f(preferably)f(also)291 4771 y Fx(k)p FC(A)p Fx(k)p FG(:)415 4958 y Fx(\017)41 b FG(The)23 b(inte)o(ger)f FC(maxit)i FG(is)g(the)f(maximum)f(number)g (of)h(iterations)f(the)i(algorithm)d(will)j(be)g(permitted)e(to)498 5057 y(perform.)415 5227 y Fx(\017)41 b FG(The)24 b(real)f(number)f Fx(k)p 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2562 y FA(\000)p Fz(1)2838 2592 y Fx(j)22 b(\001)f(j)p FC(r)2989 2562 y Fz(\()p FB(i)p Fz(\))3070 2592 y Fx(j)14 b(k)p FG(;)27 b(see)e Fx(x)p FG(4.2.3.)291 2691 y(Here)20 b Fx(j)p FC(X)7 b Fx(j)20 b FG(is)h(the)f(matrix)g(or)g (v)o(ector)f(of)g(absolute)h(v)n(alues)g(of)g(components)e(of)i FC(X)7 b FG(.\))415 2791 y(The)36 b(backw)o(ard)e(error)g(also)j(has)f (a)g(direct)f(interpretation)f(as)i(a)h(stopping)d(criterion,)k(in)e (addition)f(to)291 2891 y(supplying)28 b(a)i(bound)e(on)h(the)h(forw)o (ard)f(error)-5 b(.)53 b(Recall)31 b(that)f(the)g(backw)o(ard)e(error)h (is)i(the)f(smallest)g(change)291 2990 y Fy(max)o Fx(fk)p FC(\016)s(A)p Fx(k)p FC(=)p Fx(k)p FC(A)p Fx(k)p FC(;)14 b Fx(k)p FC(\016)s(b)p Fx(k)p FC(=)p Fx(k)p FC(b)p Fx(kg)22 b FG(to)28 b(the)f(problem)f FC(Ax)37 b Fy(=)f FC(b)28 b FG(that)g(mak)o(es)f FC(x)2561 2960 y Fz(\()p FB(i)p Fz(\))2669 2990 y FG(an)h(e)o(xact)f(solution)f(of)h Fy(\()p FC(A)e Fy(+)291 3090 y FC(\016)s(A)p Fy(\))p FC(x)472 3060 y Fz(\()p FB(i)p Fz(\))585 3090 y Fy(=)33 b FC(b)22 b Fy(+)g FC(\016)s(b)p FG(.)42 b(If)25 b(the)h(original)e (data)i FC(A)g FG(and)f FC(b)h FG(ha)n(v)o(e)f(errors)g(from)f(pre)n (vious)g(computations)g(or)h(mea-)291 3189 y(surements,)20 b(then)g(it)i(is)g(usually)f(not)f(w)o(orth)h(iterating)f(until)h FC(\016)s(A)h FG(and)f FC(\016)s(b)g FG(are)g(e)n(v)o(en)f(smaller)h (than)g(these)g(errors.)291 3289 y(F)o(or)e(e)o(xample,)e(if)j(the)f (machine)f(precision)h(is)h FC(")p FG(,)f(it)h(is)h(not)e(w)o(orth)f (making)g Fx(k)p FC(\016)s(A)p Fx(k)23 b(\024)f FC(")p Fx(k)p FC(A)p Fx(k)d FG(and)g Fx(k)p FC(\016)s(b)p Fx(k)j(\024)g FC(")p Fx(k)p FC(b)p Fx(k)p FG(,)291 3389 y(because)d(just)i(rounding)c (the)k(entries)f(of)g FC(A)h FG(and)e FC(b)i FG(to)f(\002t)h(in)f(the)h (machine)e(creates)h(errors)f(this)i(lar)o(ge.)415 3488 y(Based)30 b(on)g(this)g(discussion,)h(we)f(will)h(no)n(w)e(consider)g (some)g(stopping)g(criteria)g(and)g(their)h(properties.)291 3588 y(Abo)o(v)o(e)18 b(we)j(already)e(mentioned)291 3729 y Fv(Criterion)g(1.)41 b Fx(k)p FC(r)828 3699 y Fz(\()p FB(i)p Fz(\))908 3729 y Fx(k)e(\024)g FC(S)1144 3741 y Fz(1)1221 3729 y Fx(\021)g Ft(stop)p 1469 3729 25 4 v 30 w(tol)24 b Fx(\001)h Fy(\()p Fx(k)p FC(A)p Fx(k)g(\001)g(k)p FC(x)1994 3699 y Fz(\()p FB(i)p Fz(\))2074 3729 y Fx(k)f Fy(+)h Fx(k)p FC(b)p Fx(k)p Fy(\))p FG(.)51 b(This)30 b(is)g(equi)n(v)n(alent)d(to)i(asking)g(that)498 3829 y(the)c(backw)o(ard)f(error)g FC(\016)s(A)i FG(and)f FC(\016)s(b)g FG(described)f(abo)o(v)o(e)g(satisfy)h Fx(k)p FC(\016)s(A)p Fx(k)32 b(\024)g Ft(stop)p 2802 3829 V 29 w(tol)22 b Fx(\001)g(k)p FC(A)p Fx(k)j FG(and)g Fx(k)p FC(\016)s(b)p Fx(k)31 b(\024)498 3929 y Ft(stop)p 642 3929 V 29 w(tol)19 b Fx(\001)f(k)p FC(b)p Fx(k)p FG(.)24 b(This)d(criterion)e(yields)h(the)g(forw)o(ard)f(error)g(bound) 706 4097 y Fx(k)p FC(e)787 4063 y Fz(\()p FB(i)p Fz(\))865 4097 y Fx(k)k(\024)g(k)p FC(A)1122 4063 y FA(\000)p Fz(1)1211 4097 y Fx(k)17 b(\001)i(k)p FC(r)1393 4063 y Fz(\()p FB(i)p Fz(\))1473 4097 y Fx(k)j(\024)h Ft(stop)p 1769 4097 V 29 w(tol)18 b Fx(\001)h(k)p FC(A)2045 4063 y FA(\000)p Fz(1)2134 4097 y Fx(k)f(\001)g Fy(\()p Fx(k)p FC(A)p Fx(k)g(\001)h(k)p FC(x)2562 4063 y Fz(\()p FB(i)p Fz(\))2641 4097 y Fx(k)f Fy(+)g Fx(k)p FC(b)p Fx(k)p Fy(\))k FC(:)291 4326 y FG(The)31 b(second)g(stopping)g(criterion)g(we)h(discussed,)i (which)e(does)g(not)f(require)g Fx(k)p FC(A)p Fx(k)p FG(,)j(may)e(be)g(much)f(more)291 4426 y(stringent)19 b(than)h(Criterion)f(1:)291 4578 y Fv(Criterion)g(2.)41 b Fx(k)p FC(r)828 4548 y Fz(\()p FB(i)p Fz(\))908 4578 y Fx(k)33 b(\024)g FC(S)1132 4590 y Fz(2)1203 4578 y Fx(\021)g Ft(stop)p 1445 4578 V 29 w(tol)22 b Fx(\001)h(k)p FC(b)p Fx(k)p FG(.)41 b(This)26 b(is)h(equi)n(v)n(alent)d(to)i(asking)f (that)h(the)g(backw)o(ard)e(error)498 4677 y FC(\016)s(A)i FG(and)e FC(\016)s(b)h FG(satisfy)h FC(\016)s(A)32 b Fy(=)f(0)25 b FG(and)f Fx(k)p FC(\016)s(b)p Fx(k)31 b(\024)g FC(tol)24 b Fx(\001)e(k)p FC(b)p Fx(k)p FG(.)38 b(One)25 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y(bound)d Fx(k)p FC(e)600 2151 y Fz(\()p FB(i)p Fz(\))679 2181 y Fx(k)k(\024)h(k)p FC(A)935 2151 y FA(\000)p Fz(1)1024 2181 y FC(M)1114 2151 y Fz(1)p FB(=)p Fz(2)1218 2181 y Fx(k)18 b(\001)g(k)p FC(r)1400 2151 y Fz(\()p FB(i)p Fz(\))1480 2181 y Fx(k)1522 2200 y FB(M)1591 2184 y Fc(\000)p Fo(1)p Fn(=)p Fo(2)1727 2200 y FB(;)p Fz(2)1784 2181 y FG(,)j(which)e(could)h(also)g(be)g(used)g(in)g(a)h(stopping)e (criterion.)291 2416 y Fp(4.2.3)98 b(Estimating)25 b Fd(k)p Fe(A)1202 2379 y Fj(\000)p Fl(1)1297 2416 y Fd(k)291 2571 y FG(Bounds)g(on)g(the)h(error)f Fx(k)p FC(e)1077 2541 y Fz(\()p FB(i)p Fz(\))1155 2571 y Fx(k)h FG(ine)n(vitably)f(rely) g(on)h(bounds)e(for)h FC(A)2296 2541 y FA(\000)p Fz(1)2385 2571 y FG(,)j(since)e FC(e)2670 2541 y Fz(\()p FB(i)p Fz(\))2783 2571 y Fy(=)33 b FC(A)2943 2541 y FA(\000)p Fz(1)3032 2571 y FC(r)3071 2541 y Fz(\()p FB(i)p Fz(\))3151 2571 y FG(.)43 b(There)25 b(is)h(a)291 2671 y(lar)o(ge)19 b(number)f(of)i(problem)f(dependent)f(w)o(ays)i(to)g(estimate)h FC(A)2135 2641 y FA(\000)p Fz(1)2224 2671 y FG(;)g(we)g(mention)e(a)h (fe)n(w)g(here.)415 2770 y(When)g(a)h(splitting)f FC(A)j Fy(=)g FC(M)k Fx(\000)18 b FC(N)29 b FG(is)21 b(used)f(to)h(get)f(an)g (iteration)498 2922 y FC(x)545 2887 y Fz(\()p FB(i)p Fz(\))648 2922 y Fy(=)j FC(M)826 2887 y FA(\000)p Fz(1)915 2922 y FC(N)9 b(x)1038 2887 y Fz(\()p FB(i)p FA(\000)p Fz(1\))1221 2922 y Fy(+)18 b FC(M)1394 2887 y FA(\000)p Fz(1)1482 2922 y FC(b)23 b Fy(=)g FC(Gx)1741 2887 y Fz(\()p FB(i)p FA(\000)p Fz(1\))1924 2922 y Fy(+)18 b FC(c;)291 3073 y FG(then)h(the)h(matrix)f(whose)g(in)m(v)o(erse)g(norm)f(we)i (need)f(is)i FC(I)j Fx(\000)16 b FC(G)p FG(.)26 b(Often,)19 b(we)h(kno)n(w)f(ho)n(w)g(to)h(estimate)g Fx(k)p FC(G)p Fx(k)g FG(if)g(the)291 3173 y(splitting)f(is)i(a)f(standard)e(one)h (such)h(as)g(Jacobi)f(or)h(SOR,)g(and)f(the)h(matrix)f FC(A)h FG(has)g(special)g(characteristics)f(such)291 3272 y(as)h(Property)f(A.)i(Then)e(we)i(may)e(estimate)i Fx(k)p Fy(\()p FC(I)k Fx(\000)18 b FC(G)p Fy(\))1874 3242 y FA(\000)p Fz(1)1964 3272 y Fx(k)k(\024)h Fy(1)p FC(=)p Fy(\(1)17 b Fx(\000)h(k)p FC(G)p Fx(k)p Fy(\))p FG(.)415 3372 y(When)j FC(A)g FG(is)h(symmetric)e(positi)n(v)o(e)g (de\002nite,)g(and)h(Chebyshe)n(v)e(acceleration)g(with)i(adaptation)f (of)g(param-)291 3472 y(eters)k(is)h(being)e(used,)i(then)e(at)i(each)f (step)g(the)g(algorithm)f(estimates)i(the)f(lar)o(gest)f(and)h (smallest)h(eigen)m(v)n(alues)291 3571 y FC(\025)339 3583 y Fz(max)466 3571 y Fy(\()p FC(A)p Fy(\))c FG(and)f FC(\025)802 3583 y Fz(min)916 3571 y Fy(\()p FC(A)p Fy(\))i FG(of)e FC(A)h FG(an)o(yw)o(ay)-5 b(.)23 b(Since)d FC(A)h FG(is)h(symmetric)d(positi)n(v)o(e)g(de\002nite,)h Fx(k)p FC(A)2945 3541 y FA(\000)p Fz(1)3034 3571 y Fx(k)3076 3583 y Fz(2)3136 3571 y Fy(=)i FC(\025)3271 3536 y FA(\000)p Fz(1)3271 3595 y(min)3386 3571 y Fy(\()p FC(A)p Fy(\))p FG(.)415 3671 y(This)c(adapti)n(v)o(e)f(estimation)g(is)i(often)e(done) g(using)g(the)h Ft(Lanczos)g(algorithm)f FG(\(see)h(section)g(5.1\),)f (which)g(can)291 3770 y(usually)23 b(pro)o(vide)f(good)h(estimates)h (of)g(the)g(lar)o(gest)f(\(rightmost\))f(and)i(smallest)h(\(leftmost\)) e(eigen)m(v)n(alues)f(of)h(a)291 3870 y(symmetric)g(matrix)g(at)h(the)g (cost)g(of)g(a)g(fe)n(w)g(matrix-v)o(ector)d(multiplies.)35 b(F)o(or)24 b(general)f(nonsymmetric)e FC(A)p FG(,)26 b(we)291 3983 y(may)17 b(apply)h(the)g(Lanczos)f(method)g(to)h FC(AA)1546 3953 y FB(T)1618 3983 y FG(or)g FC(A)1768 3953 y FB(T)1820 3983 y FC(A)p FG(,)h(and)f(use)g(the)h(f)o(act)f(that) g Fx(k)p FC(A)2700 3953 y FA(\000)p Fz(1)2789 3983 y Fx(k)2831 3995 y Fz(2)2891 3983 y Fy(=)23 b(1)p FC(=\025)3111 3940 y Fz(1)p FB(=)p Fz(2)3111 4007 y(min)3224 3983 y Fy(\()p FC(AA)3380 3953 y FB(T)3433 3983 y Fy(\))h(=)291 4102 y(1)p FC(=\025)423 4059 y Fz(1)p FB(=)p Fz(2)423 4126 y(min)536 4102 y Fy(\()p FC(A)630 4072 y FB(T)683 4102 y FC(A)p Fy(\))p FG(.)415 4201 y(It)d(is)g(also)g(possible)f(to)h (estimate)f Fx(k)p FC(A)1498 4171 y FA(\000)p Fz(1)1587 4201 y Fx(k)1629 4213 y FA(1)1720 4201 y FG(pro)o(vided)e(one)i(is)h (willing)f(to)h(solv)o(e)f(a)h(fe)n(w)f(systems)h(of)f(linear)291 4301 y(equations)29 b(with)h FC(A)h FG(and)f FC(A)1124 4271 y FB(T)1208 4301 y FG(as)h(coef)n(\002cient)e(matrices.)55 b(This)31 b(is)g(often)f(done)f(with)i(dense)f(linear)g(system)291 4401 y(solv)o(ers,)h(because)d(the)i(e)o(xtra)e(cost)i(of)f(these)h (systems)g(is)g FC(O)r Fy(\()p FC(n)2185 4371 y Fz(2)2223 4401 y Fy(\))p FG(,)i(which)d(is)h(small)g(compared)e(to)h(the)h(cost) 291 4500 y FC(O)r Fy(\()p FC(n)438 4470 y Fz(3)476 4500 y Fy(\))20 b FG(of)g(the)g(LU)g(decomposition)e(\(see)i(Hager)f([120)o (],)h(Higham)f([123)n(])h(and)f(Anderson,)g Ft(et)h(al.)g FG([3)o(]\).)25 b(This)20 b(is)291 4600 y(not)g(the)g(case)h(for)f (iterati)n(v)o(e)g(solv)o(ers,)f(where)h(the)h(cost)f(of)h(these)f (solv)o(es)h(may)f(well)h(be)f(se)n(v)o(eral)g(times)h(as)g(much)291 4700 y(as)28 b(the)f(original)g(linear)g(system.)47 b(Still,)31 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3172 y Fx(k)k(\024)g FC(O)r Fy(\()p FC(")p Fy(\)\()p Fx(k)p FC(A)p Fx(k)c(\001)739 3271 y(k)p FC(x)828 3241 y Fz(\()p FB(i)p Fz(\))907 3271 y Fx(k)j Fy(+)g Fx(k)p FC(b)p Fx(k)p Fy(\))p FG(,)k(where)f FC(O)r Fy(\()p FC(")p Fy(\))i FG(is)g(typically)d(bounded)f(by)j FC(n")p FG(,)h(and)e (usually)g(closer)g(to)3379 3212 y Fx(p)p 3448 3212 50 4 v 59 x FC(n")p FG(.)44 b(This)27 b(is)g(why)739 3371 y(one)19 b(should)g(not)h(choose)f Ft(stop)p 1643 3371 25 4 v 29 w(tol)k Fx(\024)f FC(")e FG(in)h(Criterion)e(1,)h(and)f(why)g (Criterion)g(2)h(may)g(not)f(be)h(satis\002ed)h(by)e(an)o(y)739 3471 y(method.)27 b(This)21 b(uncertainty)e(in)j(the)f(v)n(alue)g(of)f FC(r)2141 3440 y Fz(\()p FB(i)p Fz(\))2244 3471 y FG(induces)g(an)h (uncertainty)e(in)j(the)f(error)f FC(e)3446 3440 y Fz(\()p FB(i)p Fz(\))3550 3471 y Fy(=)25 b FC(A)3702 3440 y FA(\000)p Fz(1)3791 3471 y FC(r)3830 3440 y Fz(\()p FB(i)p Fz(\))3933 3471 y FG(of)739 3570 y(at)e(most)g FC(O)r Fy(\()p FC(")p Fy(\))p Fx(k)p FC(A)1279 3540 y 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b(means)f(the)g(uncertainty)f(in)h FC(e)3209 3739 y Fz(\()p FB(i)p Fz(\))3313 3769 y FG(is)i(really)e(bounded)e(by) 739 3869 y FC(O)r Fy(\()p FC(")p Fy(\))p Fx(k)14 b(j)p FC(A)1048 3839 y FA(\000)p Fz(1)1138 3869 y Fx(j)6 b(\001)g Fy(\()p Fx(j)p FC(A)p Fx(j)g(\001)g(j)p FC(x)1441 3839 y Fz(\()p FB(i)p Fz(\))1521 3869 y Fx(j)g Fy(+)g Fx(j)p FC(b)p Fx(j)p Fy(\))p Fx(k)p FG(.)23 b(This)17 b(last)h(quantity)d(can) i(be)f(estimated)h(ine)o(xpensi)n(v)o(ely)d(pro)o(vided)g(solving)739 3969 y(systems)27 b(with)g FC(A)g FG(and)f FC(A)1502 3939 y FB(T)1582 3969 y FG(as)h(coef)n(\002cient)e(matrices)i(is)g(ine) o(xpensi)n(v)o(e)d(\(see)j(the)g(last)g(paragraph)d(of)i Fx(x)p FG(4.2.3\).)739 4068 y(Both)20 b(these)h(bounds)d(can)i(be)g(se) n(v)o(ere)g(o)o(v)o(erestimates)f(of)h(the)g(uncertainty)e(in)i FC(e)3043 4038 y Fz(\()p FB(i)p Fz(\))3123 4068 y FG(,)g(b)n(ut)g(e)o (xamples)f(e)o(xist)i(where)739 4168 y(the)o(y)e(are)h(attainable.)739 4455 y Fs(4.3)119 b(Data)29 b(Structur)n(es)739 4643 y FG(The)17 b(ef)n(\002cienc)o(y)f(of)h(an)o(y)f(of)h(the)g(iterati)n (v)o(e)g(methods)f(considered)f(in)j(pre)n(vious)e(sections)h(is)h (determined)d(primar)n(-)739 4743 y(ily)21 b(by)e(the)i(performance)c (of)j(the)h(matrix-v)o(ector)c(product)i(and)h(the)g(preconditioner)d (solv)o(e,)j(and)g(therefore)f(on)739 4842 y(the)e(storage)g(scheme)g (used)g(for)f(the)i(matrix)e(and)h(the)h(preconditioner)-5 b(.)21 b(Since)c(iterati)n(v)o(e)g(methods)f(are)h(typically)739 4942 y(used)g(on)g(sparse)g(matrices,)h(we)g(will)g(re)n(vie)n(w)f (here)f(a)i(number)e(of)h(sparse)g(storage)g(formats.)23 b(Often,)17 b(the)h(storage)739 5041 y(scheme)i(used)g(arises)g (naturally)f(from)g(the)i(speci\002c)f(application)f(problem.)863 5142 y(In)j(this)g(section)f(we)h(will)g(re)n(vie)n(w)f(some)g(of)h (the)f(more)g(popular)f(sparse)h(matrix)g(formats)g(that)g(are)h(used)f (in)739 5242 y(numerical)15 b(softw)o(are)h(packages)f(such)h(as)h FE(ITPACK)f FG([139)n(])h(and)f FE(NSPCG)g FG([164)n(].)24 b(After)16 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b(2)83 b Fx(\000)p Fy(1)1662 3103 y Fw(1)1662 3250 y(C)1662 3299 y(C)1662 3349 y(C)1662 3399 y(C)1662 3449 y(C)1662 3499 y(C)1662 3552 y(A)1769 3420 y FC(:)1602 b FG(\(4.1\))415 3808 y(The)26 b(CRS)j(format)c(for)h (this)i(matrix)e(is)h(then)g(speci\002ed)f(by)g(the)h(arrays)f Fx(f)p FE(val)p FG(,)i FE(col)p 2960 3808 V 29 w(ind)p FG(,)g FE(row)p 3338 3808 V 29 w(ptr)p Fx(g)291 3908 y FG(gi)n(v)o(en)18 b(belo)n(w)p 631 3977 2582 4 v 629 4077 4 100 v 860 4047 a FE(val)p 1058 4077 V 99 w FG(10)p 1241 4077 V 99 w(-2)p 1409 4077 V 99 w(3)p 1551 4077 V 99 w(9)p 1692 4077 V 99 w(3)p 1833 4077 V 99 w(7)p 1974 4077 V 99 w(8)p 2115 4077 V 100 w(7)p 2256 4077 V 99 w(3)i Fx(\001)14 b(\001)g(\001)21 b FG(9)p 2577 4077 V 99 w(13)p 2760 4077 V 98 w(4)p 2901 4077 V 100 w(2)p 3042 4077 V 99 w(-1)p 3211 4077 V 631 4080 2582 4 v 629 4180 4 100 v 681 4150 a FE(col)p 836 4150 25 4 v 29 w(ind)p 1058 4180 4 100 v 141 w FG(1)p 1241 4180 V 127 w(5)p 1409 4180 V 99 w(1)p 1551 4180 V 99 w(2)p 1692 4180 V 99 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b(dif)n(ference)f (discretization)g(on)g(a)i(tensor)f(product)e(grid.)863 3647 y(W)-7 b(e)23 b(say)g(that)f(the)f(matrix)h FC(A)k Fy(=)g(\()p FC(a)1893 3659 y FB(i;j)1971 3647 y Fy(\))d FG(is)g Ft(banded)d FG(if)i(there)f(are)h(nonne)o(gati)n(v)o(e)c (constants)k FC(p)p FG(,)g FC(q)s FG(,)h(called)e(the)739 3747 y(left)k(and)f(right)g Ft(halfbandwidth)p FG(,)g(such)g(that)h FC(a)2101 3759 y FB(i;j)2211 3747 y Fx(6)p Fy(=)31 b(0)25 b FG(only)f(if)h FC(i)d Fx(\000)f FC(p)32 b Fx(\024)f FC(j)36 b Fx(\024)c FC(i)21 b Fy(+)h FC(q)s FG(.)39 b(In)25 b(this)g(case,)h(we)f(can)739 3846 y(allocate)f(for)f(the)h(matrix)g FC(A)h FG(an)f(array)f FE(val\(1:n,-p:q\))p FG(.)34 b(The)24 b(declaration)f(with)h(re)n(v)o(ersed)e(dimensions)739 3946 y FE(\(-p:q,n\))c FG(corresponds)f(to)j(the)f FE(LINPACK)f FG(band)g(format)h([72)n(],)h(which)e(unlik)o(e)h(CDS,)h(does)f(not)g (allo)n(w)g(for)739 4046 y(an)h(ef)n(\002ciently)f(v)o(ectorizable)g (matrix-v)o(ector)e(multiplication)i(if)h Fb(p)e Fy(+)g Fb(q)j 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Fy(=)22 b Fx(f)p Fy(\()p FC(i;)14 b(\033)s Fy(\()p FC(i)p Fy(\)\);)35 b FC(i)22 b Fx(2)i FC(I)30 b Fx(\022)291 1541 y FC(I)327 1553 y FB(n)372 1541 y Fx(g)p FG(,)d(where)e FC(I)727 1553 y FB(n)806 1541 y Fy(=)33 b Fx(f)p Fy(1)p FC(;)14 b(:)g(:)g(:)f(;)h(n)p Fx(g)25 b FG(and)h FC(\033)j FG(is)e(a)f(strictly)g(increasing)f (function.)39 b(Speci\002cally)-5 b(,)26 b(if)g Fy(\()p FC(i;)14 b(\033)s Fy(\()p FC(i)p Fy(\)\))27 b FG(and)291 1640 y Fy(\()p FC(j;)14 b(\033)s Fy(\()p FC(j)5 b Fy(\)\))22 b FG(are)e(in)h FC(S)5 b FG(,)20 b(then)498 1774 y FC(i)j(<)f(j)28 b Fx(!)c FC(\033)s Fy(\()p FC(i)p Fy(\))f FC(<)g(\033)s Fy(\()p FC(j)5 b Fy(\))p FC(:)291 1908 y FG(When)21 b(computing)f(the)i (matrix-v)o(ector)d(product)h FC(y)29 b Fy(=)d FC(Ax)d FG(using)f(stripes,)g(each)g Fy(\()p FC(i;)14 b(\033)2838 1920 y FB(k)2879 1908 y Fy(\()p FC(i)p Fy(\)\))23 b FG(element)e(of)h FC(A)h FG(in)291 2007 y(stripe)c FC(S)546 2019 y FB(k)606 2007 y FG(is)h(multiplied)e(with)h(both)f FC(x)1423 2019 y 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b(addition)f(algorithm)f(then)i(becomes:)739 1631 y FE(\045)50 b(copy)f(y)g(into)g(w)739 1731 y(for)g(i=1,ly)888 1830 y(w\()h(yind\(i\))e(\))199 b(=)50 b(y\(i\))888 1930 y(wlev\()f (yind\(i\))g(\))g(=)h(ylev\(i\))739 2030 y(\045)g(add)f(w)g(to)h(x)f (wherever)g(x)g(is)h(already)e(nonzero;)739 2129 y(\045)i(don't)e (change)h(the)g(levels)739 2229 y(for)g(i=1,lx)888 2328 y(if)h(w\()f(xind\(i\))g(\))g(<>)h(0)1038 2428 y(x\(i\))f(=)g(x\(i\))h (+)f(w\()h(xind\(i\))e(\))888 2528 y(w\()i(xind\(i\))e(\))i(=)g(0)739 2627 y(\045)g(add)f(w)g(to)h(x)f(by)h(creating)e(new)h(components)739 2727 y(\045)h(wherever)e(x)h(is)h(still)f(zero;)739 2827 y(\045)h(carry)e(over)h(levels)739 2926 y(for)g(i=1,ly)888 3026 y(if)h(w\()f(yind\(i\))g(\))g(<>)h(0)f(then)1038 3126 y(lx)g(=)h(lx+1)1038 3225 y(x\(lx\))198 b(=)50 b(w\()f(yind\(i\))g (\))1038 3325 y(xind\(lx\))f(=)i(yind\(i\))1038 3424 y(xlev\(lx\))e(=)i(wlev\()f(yind\(i\))f(\))888 3524 y(endif)863 3683 y FG(W)-7 b(e)29 b(can)e(no)n(w)g(describe)g(the)g FC(I)7 b(LU)i Fy(\()p FC(k)s Fy(\))28 b FG(f)o(actorization.)44 b(The)27 b(algorithm)f(starts)i(out)f(with)h(the)f(matrix)g FE(A)p FG(,)739 3783 y(and)21 b(gradually)f(b)n(uilds)h(up)g(a)h(f)o (actorization)e FE(M)i FG(of)f(the)h(form)e FC(M)34 b Fy(=)25 b(\()p FC(D)d Fy(+)d FC(L)p Fy(\)\()p FC(I)27 b Fy(+)19 b FC(D)3266 3753 y FA(\000)p Fz(1)3355 3783 y FC(U)9 b Fy(\))p FG(,)22 b(where)f FC(L)p FG(,)h FC(D)3892 3753 y FA(\000)p Fz(1)3981 3783 y FG(,)739 3883 y(and)e FC(D)951 3853 y FA(\000)p Fz(1)1040 3883 y FC(U)29 b FG(are)20 b(stored)g(in)h(the)f(lo)n(wer)g(triangle,)f(diagonal)f(and)i (upper)f(triangle)g(of)h(the)h(array)e FE(M)h FG(respecti)n(v)o(ely)-5 b(.)739 3982 y(The)27 b(particular)g(form)g(of)g(the)h(f)o (actorization)f(is)h(chosen)f(to)h(minimize)g(the)f(number)g(of)g (times)h(that)g(the)g(full)739 4082 y(v)o(ector)19 b FE(w)h FG(is)i(copied)d(back)g(to)i(sparse)f(form.)863 4182 y(Speci\002cally)-5 b(,)20 b(we)g(use)h(a)f(sparse)g(form)g(of)f (the)i(follo)n(wing)d(f)o(actorization)h(scheme:)739 4341 y FE(for)49 b(k=1,n)888 4441 y(for)h(j=1,k-1)1038 4540 y(for)f(i=j+1,n)1187 4640 y(a\(k,i\))g(=)h(a\(k,i\))e(-)i (a\(k,j\))2384 4655 y(*)2434 4640 y(a\(j,i\))888 4739 y(for)g(j=k+1,n)1038 4839 y(a\(k,j\))e(=)i(a\(k,j\)/a\(k,k\))739 4998 y FG(This)20 b(is)h(a)g(ro)n(w-oriented)c(v)o(ersion)i(of)h(the)h (traditional)e(`left-looking')e(f)o(actorization)h(algorithm.)863 5098 y(W)-7 b(e)36 b(will)e(describe)f(an)h(incomplete)f(f)o (actorization)f(that)i(controls)f(\002ll-in)h(through)e(le)n(v)o(els)i (\(see)g(equa-)739 5198 y(tion)26 b(\(3.1\)\).)41 b(Alternati)n(v)o (ely)24 b(we)j(could)e(use)h(a)h(drop)e(tolerance)g(\(section)g (3.4.2\),)h(b)n(ut)g(this)h(is)g(less)g(attracti)n(v)o(e)739 5297 y(from)22 b(a)i(point)f(of)g(implementation.)33 b(W)m(ith)24 b(\002ll)g(le)n(v)o(els)g(we)g(can)f(perform)e(the)j(f)o (actorization)e(symbolically)g(at)739 5397 y(\002rst,)c(determining)d (storage)i(demands)e(and)i(reusing)f(this)i(information)c(through)h(a)j (number)d(of)i(linear)g(systems)739 5497 y(of)h(the)h(same)g(sparsity)f (structure.)24 b(Such)18 b(preprocessing)f(and)h(reuse)g(of)h (information)d(is)k(not)e(possible)g(with)h(\002ll)739 5596 y(controlled)f(by)i(a)h(drop)e(tolerance)g(criterium.)p eop end %%Page: 67 77 TeXDict begin 67 76 bop 291 282 a Fu(4.4.)45 b(P)-8 b(ARALLELISM)2443 b FG(67)291 515 y(The)16 b(matrix)f(arrays)h FE(A)h FG(and)f FE(M)h FG(are)f(assumed)g(to)h(be)f(in)h(compressed)e(ro)n(w)h (storage,)g(with)h(no)f(particular)f(ordering)291 615 y(of)h(the)g(elements)g(inside)g(each)g(ro)n(w)-5 b(,)16 b(b)n(ut)g(arrays)f FE(adiag)h FG(and)g FE(mdiag)g FG(point)f(to)h(the) h(locations)e(of)h(the)g(diagonal)291 715 y(elements.)291 902 y FE(for)49 b(row=1,n)291 1001 y(\045)99 b(go)49 b(through)g(elements)f(A\(row,col\))g(with)h(col)i(row)739 2496 y(M\(col\))f(=)g(M\(col\))1536 2511 y(*)1636 2496 y(M\(mdiag\(row\)\))415 2682 y FG(The)29 b(structure)f(of)h(a)g(particular)f(sparse)h(matrix)f(is)i(lik)o(ely)f (to)h(apply)e(to)h(a)g(sequence)f(of)h(problems,)h(for)291 2781 y(instance)22 b(on)g(dif)n(ferent)e(time-steps,)j(or)f(during)f(a) i(Ne)n(wton)e(iteration.)31 b(Thus)22 b(it)h(may)f(pay)g(of)n(f)g(to)h (perform)d(the)291 2881 y(abo)o(v)o(e)25 b(incomplete)h(f)o (actorization)f(\002rst)j(symbolically)e(to)h(determine)f(the)h(amount) f(and)h(location)f(of)h(\002ll-in)291 2981 y(and)21 b(use)h(this)g (structure)f(for)g(the)g(numerically)f(dif)n(ferent)g(b)n(ut)i (structurally)f(identical)g(matrices.)29 b(In)21 b(this)i(case,)291 3080 y(the)e(array)f(for)g(the)h(numerical)f(v)n(alues)g(can)h(be)g (used)g(to)g(store)g(the)g(le)n(v)o(els)g(during)f(the)h(symbolic)f(f)o (actorization)291 3180 y(phase.)291 3465 y Fs(4.4)119 b(P)o(arallelism)291 3652 y FG(In)19 b(this)i(section)f(we)h(discuss)f (aspects)h(of)f(parallelism)f(in)i(the)f(iterati)n(v)o(e)f(methods)h (discussed)g(in)g(this)h(book.)415 3753 y(Since)30 b(the)g(iterati)n(v) o(e)f(methods)f(share)i(most)g(of)f(their)g(computational)f(k)o(ernels) h(we)h(will)h(discuss)f(these)291 3852 y(independent)17 b(of)j(the)g(method.)k(The)c(basic)g(time-consuming)d(k)o(ernels)j(of)g (iterati)n(v)o(e)g(schemes)g(are:)415 4021 y Fx(\017)41 b FG(inner)19 b(products,)415 4191 y Fx(\017)41 b FG(v)o(ector)19 b(updates,)415 4360 y Fx(\017)41 b FG(matrix\226v)o(ector)17 b(products,)i(e.g.,)g FC(Ap)1576 4330 y Fz(\()p FB(i)p Fz(\))1677 4360 y FG(\(for)g(some)h(methods)f(also)h FC(A)2536 4330 y FB(T)2589 4360 y FC(p)2631 4330 y Fz(\()p FB(i)p Fz(\))2710 4360 y FG(\),)415 4530 y Fx(\017)41 b FG(preconditioner)17 b(solv)o(es.)415 4698 y(W)-7 b(e)27 b(will)f(e)o(xamine)e(each)h(of)g(these)h(in)g(turn.)40 b(W)-7 b(e)26 b(will)h(conclude)c(this)j(section)g(by)f(discussing)g (tw)o(o)g(par)n(-)291 4798 y(ticular)f(issues,)j(namely)d (computational)e(w)o(a)n(v)o(efronts)i(in)h(the)g(SOR)h(method,)e(and)h (block)f(operations)f(in)i(the)291 4898 y(GMRES)20 b(method.)291 5140 y Fp(4.4.1)98 b(Inner)26 b(pr)n(oducts)291 5297 y FG(The)k(computation)f(of)i(an)g(inner)f(product)f(of)i(tw)o(o)g(v)o (ectors)f(can)h(be)g(easily)g(parallelized;)36 b(each)30 b(processor)291 5397 y(computes)g(the)j(inner)e(product)f(of)i (corresponding)d(se)o(gments)i(of)h(each)g(v)o(ector)f(\(local)g(inner) h(products)e(or)291 5497 y(LIPs\).)44 b(On)26 b(distrib)n(uted-memory)d (machines)j(the)g(LIPs)h(then)f(ha)n(v)o(e)g(to)h(be)f(sent)h(to)g (other)f(processors)f(to)i(be)291 5596 y(combined)18 b(for)i(the)h(global)f(inner)f(product.)25 b(This)c(can)f(be)h(done)e (either)h(with)h(an)g(all-to-all)f(send)g(where)g(e)n(v)o(ery)p eop end %%Page: 68 78 TeXDict begin 68 77 bop 739 282 a FG(68)2004 b Fu(CHAPTER)21 b(4.)46 b(RELA)-9 b(TED)20 b(ISSUES)739 515 y FG(processor)31 b(performs)f(the)j(summation)d(of)i(the)h(LIPs,)i(or)d(by)g(a)h(global) e(accumulation)f(in)i(one)g(processor)m(,)739 615 y(follo)n(wed)19 b(by)g(a)i(broadcast)e(of)h(the)g(\002nal)g(result.)25 b(Clearly)-5 b(,)20 b(this)h(step)f(requires)f(communication.)863 720 y(F)o(or)j(shared-memory)d(machines,)j(the)g(accumulation)e(of)i (LIPs)h(can)f(be)g(implemented)e(as)j(a)g(critical)f(sec-)739 819 y(tion)j(where)h(all)g(processors)f(add)g(their)h(local)g(result)f (in)h(turn)g(to)g(the)f(global)g(result,)i(or)f(as)g(a)h(piece)e(of)h (serial)739 919 y(code,)19 b(where)h(one)f(processor)g(performs)g(the)h (summations.)739 1168 y Fv(Ov)o(erlapping)f(communication)h(and)g (computation)739 1333 y FG(Clearly)-5 b(,)26 b(in)f(the)h(usual)f (formulation)e(of)i(conjugate)e(gradient-type)g(methods)h(the)h(inner)g (products)f(induce)g(a)739 1433 y(synchronization)d(of)k(the)f (processors,)g(since)h(the)o(y)f(cannot)f(progress)h(until)g(the)g (\002nal)h(result)g(has)f(been)g(com-)739 1533 y(puted:)j(updating)20 b FC(x)1335 1503 y Fz(\()p FB(i)p Fz(+1\))1522 1533 y FG(and)h FC(r)1703 1503 y Fz(\()p FB(i)p Fz(+1\))1890 1533 y FG(can)g(only)g(be)o(gin)g(after)g(completing)f(the)i(inner)f 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FB(T)1977 1472 y FG(form,)f(and)g(nonsymmetric)e(preconditioners)g(in)j(the)291 1571 y(Biconjugate)18 b(Gradient)h(Method.)291 1787 y Fv(F)n(ewer)h(synchr)o(onization)e(points)291 1943 y FG(Se)n(v)o(eral)24 b(authors)f(ha)n(v)o(e)i(found)e(w)o(ays)i(to)g (eliminate)f(some)h(of)f(the)h(synchronization)d(points)i(induced)f(by) i(the)291 2042 y(inner)19 b(products)f(in)i(methods)f(such)g(as)i(CG.)f (One)g(strate)o(gy)f(has)h(been)f(to)h(replace)f(one)g(of)h(the)f(tw)o (o)i(inner)e(prod-)291 2142 y(ucts)24 b(typically)f(present)g(in)h (conjugate)e(gradient-lik)o(e)g(methods)h(by)h(one)f(or)h(tw)o(o)g (others)g(in)g(such)f(a)i(w)o(ay)f(that)291 2241 y(all)d(inner)g (products)f(can)h(be)g(performed)e(simultaneously)-5 b(.)26 b(The)21 b(global)f(communication)f(can)i(then)g(be)g(pack-)291 2341 y(aged.)26 b(A)21 b(\002rst)h(such)e(method)g(w)o(as)i(proposed)c (by)j(Saad)g([181)n(])g(with)g(a)g(modi\002cation)e(to)i(impro)o(v)o(e) e(its)j(stability)291 2441 y(suggested)d(by)i(Meurant)f([155)n(].)27 b(Recently)-5 b(,)20 b(related)h(methods)f(ha)n(v)o(e)g(been)g (proposed)f(by)h(Chronopoulos)e(and)291 2540 y(Gear)j([54)o(],)h(D'Aze) n(v)o(edo)d(and)i(Romine)g([61)o(],)h(and)f(Eijkhout)f([87)n(].)30 b(These)21 b(schemes)g(can)h(also)g(be)f(applied)g(to)291 2640 y(nonsymmetric)g(methods)h(such)i(as)g(BiCG.)h(The)e(stability)h (of)f(such)h(methods)e(is)j(discussed)e(by)g(D'Aze)n(v)o(edo,)291 2740 y(Eijkhout)18 b(and)i(Romine)g([60)n(].)415 2839 y(Another)c(approach)g(is)i(to)g(generate)e(a)i(number)e(of)h(successi) n(v)o(e)g(Krylo)o(v)f(v)o(ectors)h(\(see)g Fx(x)p FG(2.3.4\))f(and)h (orthog-)291 2939 y(onalize)i(these)h(as)h(a)g(block)e(\(see)i(V)-9 b(an)19 b(Rosendale)h([208)n(],)g(and)g(Chronopoulos)d(and)j(Gear)g ([54)o(]\).)291 3171 y Fp(4.4.2)98 b(V)-10 b(ector)26 b(updates)291 3326 y FG(V)-9 b(ector)19 b(updates)g(are)i(tri)n(vially) e(parallelizable:)24 b(each)c(processor)f(updates)g(its)j(o)n(wn)d(se)o (gment.)291 3558 y Fp(4.4.3)98 b(Matrix-v)o(ector)26 b(pr)n(oducts)291 3714 y FG(The)31 b(matrix\226v)o(ector)e(products)i (are)h(often)f(easily)i(parallelized)d(on)i(shared-memory)d(machines)i (by)h(split-)291 3814 y(ting)23 b(the)g(matrix)g(in)h(strips)g (corresponding)c(to)j(the)h(v)o(ector)e(se)o(gments.)34 b(Each)23 b(processor)g(then)g(computes)f(the)291 3913 y(matrix\226v)o(ector)e(product)i(of)i(one)f(strip.)36 b(F)o(or)23 b(distrib)n(uted-memory)e(machines,)i(there)g(may)h(be)f(a) i(problem)d(if)291 4013 y(each)j(processor)g(has)h(only)f(a)i(se)o (gment)e(of)g(the)h(v)o(ector)f(in)h(its)h(memory)-5 b(.)41 b(Depending)24 b(on)h(the)h(bandwidth)e(of)291 4113 y(the)c(matrix,)f(we)i(may)f(need)g(communication)d(for)j(other)f (elements)h(of)g(the)h(v)o(ector)m(,)d(which)i(may)g(lead)g(to)h(com-) 291 4212 y(munication)26 b(bottlenecks.)46 b(Ho)n(we)n(v)o(er)m(,)28 b(man)o(y)f(sparse)h(matrix)f(problems)f(arise)j(from)d(a)j(netw)o(ork) d(in)i(which)291 4312 y(only)21 b(nearby)g(nodes)g(are)i(connected.)29 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b(methods)f(discussed)h(so)g(f)o(ar)g(are)g(all)h (subspace)e(methods,)h(that)g(is,)i(in)e(e)n(v)o(ery)f(iteration)g(the) o(y)g(e)o(xtend)g(the)739 2558 y(dimension)d(of)i(the)g(subspace)f (generated.)29 b(In)22 b(f)o(act,)g(the)o(y)g(generate)e(an)i (orthogonal)e(basis)i(for)g(this)g(subspace,)739 2657 y(by)e(orthogonalizing)c(the)k(ne)n(wly)g(generated)e(v)o(ector)h(with) i(respect)f(to)g(the)g(pre)n(vious)f(basis)i(v)o(ectors.)863 2757 y(Ho)n(we)n(v)o(er)m(,)f(in)i(the)f(case)h(of)f(nonsymmetric)e (coef)n(\002cient)i(matrices)g(the)g(ne)n(wly)g(generated)f(v)o(ector)g (may)h(be)739 2857 y(almost)c(linearly)f(dependent)f(on)h(the)h(e)o (xisting)f(basis.)25 b(T)-7 b(o)17 b(pre)n(v)o(ent)e(break-do)n(wn)f (or)j(se)n(v)o(ere)f(numerical)f(error)h(in)739 2956 y(such)g(instances,)h(methods)e(ha)n(v)o(e)h(been)g(proposed)e(that)j (perform)d(a)j(look-ahead)d(step)i(\(see)h(Freund,)f(Gutknecht)739 3056 y(and)k(Nachtigal)f([100)n(],)h(P)o(arlett,)g(T)-7 b(aylor)19 b(and)h(Liu)g([171)n(],)h(and)e(Freund)g(and)h(Nachtigal)f ([101)n(]\).)863 3155 y(Se)n(v)o(eral)26 b(ne)n(w)-5 b(,)27 b(unorthogonalized,)d(basis)j(v)o(ectors)e(are)i(generated)e (and)h(are)g(then)g(orthogonalized)d(with)739 3255 y(respect)c(to)g (the)g(subspace)g(already)f(generated.)23 b(Instead)18 b(of)h(generating)f(a)h(basis,)h(such)f(a)h(method)e(generates)g(a)739 3355 y(series)j(of)f(lo)n(w-dimensional)d(orthogonal)h(subspaces.)863 3454 y(The)29 b FC(s)p FG(-step)g(iterati)n(v)o(e)g(methods)f(of)h (Chronopoulos)e(and)h(Gear)h([54)o(])h(use)f(this)h(strate)o(gy)e(of)h (generating)739 3554 y(unorthogonalized)22 b(v)o(ectors)k(and)h (processing)e(them)i(as)g(a)g(block)f(to)h(reduce)f(computational)f(o)o (v)o(erhead)f(and)739 3654 y(impro)o(v)o(e)18 b(processor)h(cache)g (beha)n(viour)-5 b(.)863 3753 y(If)29 b(conjugate)f(gradient)f(methods) i(are)g(considered)e(to)i(generate)f(a)i(f)o(actorization)d(of)i(a)h (tridiagonal)e(re-)739 3853 y(duction)22 b(of)i(the)g(original)e 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y(v)o(ector)19 b FC(v)1006 4202 y FB(B)1084 4190 y FG(de\002ned)g(on)h FC(B)25 b FG(as)c(follo)n(ws:)946 4358 y FC(K)1023 4323 y FA(\000)p Fz(1)1017 4383 y FB(B)s(P)9 b(S)1169 4358 y FC(v)1209 4370 y FB(B)1290 4358 y Fy(=)22 b FC(R)1441 4324 y FB(T)1440 4379 y(H)1503 4358 y FC(A)1565 4323 y FA(\000)p Fz(1)1565 4383 y FB(H)1655 4358 y FC(R)1718 4370 y FB(H)1781 4358 y FC(v)1821 4370 y FB(B)1897 4358 y Fy(+)1980 4280 y Fw(X)2002 4458 y FB(E)2051 4466 y Fn(i)2113 4358 y FC(R)2177 4324 y FB(T)2176 4379 y(E)2225 4387 y Fn(i)2256 4358 y FC(M)2346 4323 y FA(\000)p Fz(1)2337 4383 y FB(E)2386 4391 y Fn(i)2434 4358 y FC(R)2497 4370 y FB(E)2546 4378 y Fn(i)2577 4358 y FC(v)2617 4370 y FB(B)2674 4358 y FC(:)1104 b FG(\(5.10\))863 4600 y(Analogous)16 b(to)i(the)g(additi)n(v)o(e)e(Schw)o(arz)i(preconditioner)m(,)c(the)k (computation)d(of)j(each)f(term)h(consists)g(of)f(the)739 4700 y(three)25 b(steps)g(of)g(restriction-in)m(v)o (ersion-interpolatio)o(n)20 b(and)k(is)i(independent)d(of)i(the)g 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y(mon)c(v)o(erte)o(x)f FC(V)1172 5409 y FB(k)1213 5397 y FG(,)j(which)e(is)h(not)f(accounted)f (for)h(in)h FC(K)2281 5409 y FB(B)s(P)9 b(S)2432 5397 y FG(.)24 b(Smith)16 b([190)n(])g(proposed)d(a)j Ft(verte)n(x)g(space)f FG(modi\002ca-)739 5497 y(tion)21 b(to)g FC(K)1047 5509 y FB(B)s(P)9 b(S)1220 5497 y FG(which)20 b(e)o(xplicitly)g(accounts)g (for)g(this)i(coupling)d(and)h(therefore)f(eliminates)i(the)g (dependence)739 5596 y(on)i FC(H)30 b FG(and)23 b FC(h)p FG(.)34 b(The)23 b(idea)g(is)h(to)f(introduce)e(further)h(subsets)h(of) g FC(B)28 b FG(called)23 b Ft(verte)n(x)h(spaces)f FC(X)35 b Fy(=)3597 5534 y Fw(S)3666 5621 y FB(k)3721 5596 y FC(X)3790 5608 y FB(k)3854 5596 y FG(with)p eop end %%Page: 79 89 TeXDict begin 79 88 bop 291 282 a Fu(5.4.)45 b(DOMAIN)20 b(DECOMPOSITION)f(METHODS)1546 b FG(79)291 515 y FC(X)360 527 y FB(k)425 515 y FG(consisting)23 b(of)g(a)i(small)f(set)h(of)e(v)o (ertices)h(on)f(the)h(edges)g(incident)f(on)g(the)h(v)o(erte)o(x)e FC(V)2886 527 y FB(k)2952 515 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1013 y(the)24 b(literature)g(\(see)h(Chan,)g(Mathe)n(w)f(and)g(Shao)g([51)o(]\).)38 b(W)-7 b(e)26 b(shall)f(let)g FC(M)2485 1025 y FB(X)2539 1034 y Fn(k)2604 1013 y FG(be)g(such)f(a)h(preconditioner)d(for)291 1113 y FC(S)342 1125 y FB(X)396 1134 y Fn(k)436 1113 y FG(.)k(Then)19 b(Smith')-5 b(s)21 b(V)-9 b(erte)o(x)19 b(Space)h(preconditioner)d(is)k(de\002ned)e(by:)498 1320 y FC(K)575 1285 y FA(\000)p Fz(1)569 1345 y FB(V)14 b(S)670 1320 y FC(v)710 1332 y FB(B)851 1320 y Fy(=)82 b FC(R)1062 1286 y FB(T)1061 1341 y(H)1124 1320 y FC(A)1186 1285 y FA(\000)p Fz(1)1186 1345 y FB(H)1276 1320 y FC(R)1339 1332 y FB(H)1402 1320 y FC(v)1442 1332 y FB(B)1517 1320 y Fy(+)1601 1242 y Fw(X)1623 1420 y FB(E)1672 1428 y Fn(i)1734 1320 y FC(R)1798 1286 y FB(T)1797 1341 y(E)1846 1349 y Fn(i)1877 1320 y FC(M)1967 1285 y FA(\000)p Fz(1)1958 1345 y FB(E)2007 1353 y Fn(i)2055 1320 y FC(R)2118 1332 y FB(E)2167 1340 y Fn(i)2197 1320 y FC(v)2237 1332 y FB(B)1017 1557 y Fy(+)1100 1478 y Fw(X)1114 1656 y FB(X)1168 1665 y Fn(k)1233 1557 y FC(R)1297 1522 y FB(T)1296 1577 y(X)1350 1586 y Fn(k)1391 1557 y FC(M)1481 1521 y FA(\000)p Fz(1)1472 1581 y FB(X)1526 1590 y Fn(k)1570 1557 y FC(R)1633 1569 y FB(X)1687 1578 y Fn(k)1728 1557 y FC(v)1768 1569 y FB(B)1825 1557 y FC(:)1505 b FG(\(5.11\))291 1845 y(Smith)28 b([190)n(])h(pro)o(v)o(ed)d(that)i(the)g(condition)f(number)f(of)i FC(K)2067 1809 y FA(\000)p Fz(1)2061 1869 y FB(V)14 b(S)2163 1845 y FC(S)2214 1857 y FB(B)2299 1845 y FG(is)30 b(bounded)c (independent)f(of)j FC(H)36 b FG(and)28 b FC(h)p FG(,)291 1945 y(pro)o(vided)17 b(there)j(is)h(suf)n(\002cient)f(o)o(v)o(erlap)e (of)i FC(X)1622 1957 y FB(k)1683 1945 y FG(with)h FC(B)t FG(.)291 2227 y Fp(5.4.3)98 b(Further)27 b(Remarks)291 2398 y Fv(Multiplicati)o(v)o(e)20 b(Schwarz)g(Methods)291 2569 y FG(As)h(mentioned)d(before,)h(the)h(Additi)n(v)o(e)f(Schw)o(arz) h(preconditioner)d(can)k(be)f(vie)n(wed)f(as)j(an)e(o)o(v)o(erlapping)d (block)291 2668 y(Jacobi)i(preconditioner)-5 b(.)22 b(Analogously)-5 b(,)17 b(one)i(can)g(de\002ne)g(a)h Ft(multiplicative)f FG(Schw)o(arz)g(preconditioner)d(which)291 2768 y(corresponds)h(to)i(a) h(symmetric)f(block)f(Gauss-Seidel)i(v)o(ersion.)j(That)c(is,)h(the)g (solv)o(es)f(on)g(each)h(subdomain)d(are)291 2868 y(performed)23 b(sequentially)-5 b(,)25 b(using)g(the)h(most)g(current)e(iterates)j (as)f(boundary)d(conditions)h(from)h(neighboring)291 2967 y(subdomains.)55 b(Ev)o(en)30 b(without)g(conjugate)f(gradient)h (acceleration,)i(the)f(multiplicati)n(v)o(e)e(method)h(can)h(tak)o(e) 291 3067 y(man)o(y)g(fe)n(wer)h(iterations)g(than)g(the)g(additi)n(v)o (e)f(v)o(ersion.)61 b(Ho)n(we)n(v)o(er)m(,)33 b(the)g(multiplicati)n(v) o(e)e(v)o(ersion)g(is)i(not)f(as)291 3166 y(parallelizable,)22 b(although)f(the)j(de)o(gree)d(of)i(parallelism)g(can)g(be)g(increased) f(by)h(trading)f(of)n(f)h(the)g(con)m(v)o(er)o(gence)291 3266 y(rate)d(through)e(multi-coloring)f(the)j(subdomains.)k(The)19 b(theory)g(can)h(be)g(found)f(in)h(Bramble,)g Ft(et)g(al.)h FG([37)n(].)291 3532 y Fv(Inexact)e(Solv)o(es)291 3703 y FG(The)24 b(e)o(xact)h(solv)o(es)g(in)m(v)n(olving)e FC(A)1278 3672 y FA(0)1302 3661 y(\000)p Fz(1)1302 3723 y FB(i)1391 3703 y FC(;)14 b(A)1490 3667 y FA(\000)p Fz(1)1490 3726 y FB(i)1605 3703 y FG(and)24 b FC(A)1812 3667 y FA(\000)p Fz(1)1812 3727 y FB(H)1927 3703 y FG(in)i FC(K)2089 3715 y FB(as)2160 3703 y FC(;)14 b(K)2268 3715 y FB(B)s(P)9 b(S)2419 3703 y FC(;)14 b(K)2527 3715 y FB(V)g(S)2654 3703 y FG(can)25 b(be)g(replaced)f(by)h(ine)o(xact)291 3829 y(solv)o(es)540 3808 y Fy(~)518 3829 y FC(A)580 3805 y FA(0)603 3773 y(\000)p Fz(1)603 3849 y FB(i)693 3829 y FC(;)751 3808 y Fy(~)730 3829 y FC(A)792 3793 y FA(\000)p Fz(1)792 3852 y FB(i)902 3829 y FG(and)1065 3808 y Fy(~)1043 3829 y FC(A)1105 3793 y FA(\000)p Fz(1)1105 3853 y FB(H)1194 3829 y FG(,)c(which)f(can)g(be)h(standard)e(elliptic)i (preconditioners)c(themselv)o(es)j(\(e.g.)25 b(multi-)291 3928 y(grid,)19 b(ILU,)h(SSOR,)h(etc.\).)415 4036 y(F)o(or)26 b(the)h(Schw)o(arz)f(methods,)h(the)g(modi\002cation)e(is)i (straightforw)o(ard)d(and)i(the)h Ft(Ine)n(xact)f(Solve)g(Additive)291 4136 y(Sc)o(hwarz)19 b(Pr)m(econditioner)i FG(is)g(simply:)1220 4381 y Fy(~)1197 4402 y FC(K)1274 4368 y FA(\000)p Fz(1)1268 4423 y FB(as)1363 4402 y FC(v)26 b Fy(=)d FC(R)1581 4368 y FB(T)1580 4423 y(H)1665 4381 y Fy(~)1643 4402 y FC(A)1705 4367 y FA(\000)p Fz(1)1705 4427 y FB(H)1794 4402 y FC(R)1857 4414 y FB(H)1920 4402 y FC(v)f Fy(+)2108 4294 y FB(p)2065 4323 y Fw(X)2071 4500 y FB(i)p Fz(=1)2199 4402 y FC(R)2263 4368 y FB(T)2262 4423 y(i)2337 4381 y Fy(~)2315 4402 y FC(A)2377 4378 y FA(0)2400 4346 y(\000)p Fz(1)2400 4423 y FB(i)2489 4402 y FC(R)2552 4414 y FB(i)2580 4402 y FC(v)s(:)415 4681 y FG(The)28 b(Schur)g(Complement)g(methods)f (require)h(more)f(changes)h(to)h(accommodate)d(ine)o(xact)i(solv)o(es.) 50 b(By)291 4780 y(replacing)26 b FC(A)690 4745 y FA(\000)p Fz(1)690 4805 y FB(H)808 4780 y FG(by)942 4759 y Fy(~)920 4780 y FC(A)982 4745 y FA(\000)p 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FC(x)24 b Fy(=)e FC(A)799 3216 y FB(i)827 3204 y Fy(\()p FC(A)921 3169 y FB(T)921 3224 y(i)974 3204 y FC(A)1036 3216 y FB(i)1064 3204 y Fy(\))1096 3169 y FA(\000)p Fz(1)1185 3204 y FC(A)1247 3169 y FB(T)1247 3224 y(i)1300 3204 y FC(x:)291 3370 y FG(These)e(methods)f(ha)n(v)o(e)h(good)f(parallel)h (properties)f(and)g(seem)i(to)f(be)h(rob)n(ust)e(in)i(handling)d (nonsymmetric)g(and)291 3469 y(inde\002nite)h(problems.)415 3569 y(Ro)n(w)25 b(projection)d(methods)h(can)h(be)g(used)g(as)h (preconditioners)c(in)k(the)f(conjugate)e(gradient)h(method.)35 b(In)291 3668 y(that)19 b(case,)h(there)g(is)g(a)h(theoretical)d (connection)g(with)i(the)g(conjugate)d(gradient)i(method)f(on)i(the)f (normal)g(equa-)291 3768 y(tions)h(\(see)g Fx(x)p FG(2.3.3\).)p eop end %%Page: 82 92 TeXDict begin 82 91 bop 739 282 a FG(82)1891 b Fu(CHAPTER)21 b(5.)45 b(REMAINING)20 b(T)o(OPICS)p eop end %%Page: 83 93 TeXDict begin 83 92 bop 291 1139 a FD(A)l(ppendix)42 b(A)291 1554 y FF(Obtaining)52 b(the)f(Softwar)l(e)291 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b(SGEMV\()e('N',)h(M,)h(N,)f(ONE,)g(A,)h (LDA,)f(X,)g(1,)h(ONE,)f(B,)g(1)h(\))96 b FG(computes)946 615 y(the)21 b(matrix-v)o(ector)c(product)h(plus)j(v)o(ector)e FC(Ax)g Fy(+)f FC(b)p FG(,)i(putting)f(the)h(resulting)f(v)o(ector)g (in)i FC(b)p FG(.)946 748 y(The)f(corresponding)d(F)o(ortran)i(se)o (gment:)946 947 y FE(DO)50 b(J)g(=)f(1,)h(N)1096 1047 y(DO)f(I)h(=)g(1,)f(M)1245 1146 y(B\(I\))g(=)h(A\(I,J\))1894 1161 y(*)1944 1146 y(X\(J\))e(+)h(B\(I\))1096 1246 y(ENDDO)946 1346 y(ENDDO)946 1545 y FG(This)26 b(illustrates)g(a)f(feature)g(of)g (the)g(BLAS)h(that)f(often)g(requires)f(close)i(attention.)39 b(F)o(or)25 b(e)o(xample,)g(we)946 1644 y(will)e(use)f(this)g(routine)f (to)h(compute)e(the)i(residual)f(v)o(ector)g FC(b)e Fx(\000)h FC(A)5 b Fy(^)-47 b FC(x)p FG(,)23 b(where)j Fy(^)-47 b FC(x)23 b FG(is)g(our)e(current)f(approxi-)946 1744 y(mation)j(to)g(the)f(solution)g FC(x)i FG(\(merely)e(change)g(the)g (fourth)g(ar)o(gument)e(to)j FE(-1.0E0)p FG(\).)32 b(V)-9 b(ector)23 b FC(b)g 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b(feature)e(will)i (be)g(used)f(e)o(xtensi)n(v)o(ely)-5 b(,)22 b(resulting)g(in)i(storage) 739 3438 y(sa)n(vings)c(\(among)e(other)i(adv)n(antages\).)863 3537 y(The)25 b(v)n(ariable)g FE(LDA)g FG(is)h(critical)g(for)e (addressing)g(the)i(array)e(correctly)-5 b(.)39 b FE(LDA)25 b FG(is)h(the)f(leading)g(dimension)739 3637 y(of)f(the)g(tw)o (o-dimensional)e(array)h FE(A)p FG(,)i(that)f(is,)i FE(LDA)e FG(is)i(the)e Ft(declar)m(ed)f FG(\(or)h(allocated\))f(number)f(of)i (ro)n(ws)g(of)g(the)739 3737 y(tw)o(o-dimensional)18 b(array)h FC(A)p FG(.)p eop end %%Page: 87 97 TeXDict begin 87 96 bop 291 1138 a FD(A)l(ppendix)42 b(C)291 1553 y FF(Glossary)291 1985 y Fv(Adapti)o(v)o(e)20 b(methods)41 b FG(Iterati)n(v)o(e)22 b(methods)h(that)h(collect)g (information)d(about)i(the)h(coef)n(\002cient)e(matrix)i(during)498 2084 y(the)c(iteration)g(process,)f(and)h(use)g(this)h(to)f(speed)g(up) g(con)m(v)o(er)o(gence.)291 2243 y Fv(Backward)g(err)o(or)40 b FG(The)25 b(size)g(of)g(perturbations)e 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b(this)i(section,)e (we)i(present)e(some)h(of)f(the)h(notation)f(we)h(use)g(throughout)d (the)j(book.)29 b(W)-7 b(e)23 b(ha)n(v)o(e)e(tried)h(to)g(use)291 4561 y(standard)d(notation)g(that)h(w)o(ould)f(be)h(found)f(in)h(an)o (y)g(current)e(publication)h(on)h(the)g(subjects)g(co)o(v)o(ered.)415 4666 y(Throughout,)d(we)j(follo)n(w)g(se)n(v)o(eral)f(con)m(v)o (entions:)415 4848 y Fx(\017)41 b FG(Matrices)20 b(are)h(denoted)d(by)i (capital)g(letters.)415 5035 y Fx(\017)41 b FG(V)-9 b(ectors)20 b(are)g(denoted)f(by)g(lo)n(wercase)h(letters.)415 5222 y Fx(\017)41 b FG(Lo)n(wercase)19 b(greek)h(letters)g(usually)g(denote) f(scalars,)h(for)g(instance)415 5409 y Fx(\017)41 b FG(Matrix)20 b(elements)g(are)g(denoted)e(by)i(doubly)f(inde)o(x)o(ed)f(lo)n (wercase)h(letter)m(,)h(ho)n(we)n(v)o(er)415 5596 y Fx(\017)41 b FG(Matrix)20 b(subblocks)f(are)h(denoted)e(by)i(doubly)f(inde)o(x)o (ed)f(uppercase)g(letters.)p eop end %%Page: 92 102 TeXDict begin 92 101 bop 739 282 a FG(92)2197 b Fu(APPENDIX)20 b(C.)42 b(GLOSSAR)-5 b(Y)863 515 y FG(W)e(e)22 b(de\002ne)d(matrix)h FC(A)h FG(of)f(dimension)f FC(m)f Fx(\002)g FC(n)j FG(and)e(block)g (dimension)g FC(m)3024 485 y FA(0)3066 515 y Fx(\002)f FC(n)3199 485 y FA(0)3243 515 y FG(as)j(follo)n(ws:)946 795 y FC(A)j Fy(=)1119 603 y Fw(2)1119 749 y(6)1119 802 y(4)1229 667 y FC(a)1273 679 y Fz(1)p FB(;)p Fz(1)1459 667 y Fx(\001)14 b(\001)g(\001)96 b FC(a)1696 679 y Fz(1)p FB(;n)1286 755 y FG(.)1286 788 y(.)1286 821 y(.)1712 755 y(.)1712 788 y(.)1712 821 y(.)1216 921 y FC(a)1260 933 y FB(m;)p Fz(1)1459 921 y Fx(\001)14 b(\001)g(\001)83 b FC(a)1683 933 y FB(m;n)1848 603 y Fw(3)1848 749 y(7)1848 802 y(5)2083 795 y Fy(\()p FC(a)2159 807 y FB(i;j)2261 795 y Fx(2)23 b(R)p Fy(\))2622 603 y Fw(2)2622 749 y(6)2622 802 y(4)2743 667 y FC(A)2805 679 y Fz(1)p FB(;)p Fz(1)3002 667 y Fx(\001)14 b(\001)g(\001)107 b FC(A)3268 679 y Fz(1)p FB(;n)3362 663 y Fc(0)2809 755 y FG(.)2809 788 y(.)2809 821 y(.)3287 755 y(.)3287 788 y(.)3287 821 y(.)2719 921 y FC(A)2781 933 y FB(m)2840 917 y Fc(0)2862 933 y FB(;)p Fz(1)3002 921 y Fx(\001)14 b(\001)g(\001)83 b FC(A)3244 933 y FB(m)3303 917 y Fc(0)3326 933 y FB(;n)3387 917 y Fc(0)3455 603 y Fw(3)3455 749 y(7)3455 802 y(5)3690 795 y Fy(\()p FC(A)3784 807 y FB(i;j)3886 795 y Fx(2)23 b(R)4034 760 y FA(m)4075 771 y Fc(i)4105 760 y FA(\002n)4191 771 y Fc(i)4224 795 y Fy(\))p FC(:)863 1082 y FG(W)-7 b(e)22 b(de\002ne)d(v)o(ector)g FC(x)j FG(of)e(dimension)e FC(n)j FG(as)g(follo)n(ws:)946 1356 y FC(x)j Fy(=)1105 1164 y Fw(2)1105 1310 y(6)1105 1363 y(4)1205 1228 y FC(x)1252 1240 y Fz(1)1237 1316 y FG(.)1237 1349 y(.)1237 1382 y(.)1201 1482 y FC(x)1248 1494 y FB(n)1336 1164 y Fw(3)1336 1310 y(7)1336 1363 y(5)1571 1356 y FC(x)1618 1368 y FB(i)1669 1356 y Fx(2)f(R)p FC(:)863 1643 y FG(Other)d(notation)f(is)i(as)g (follo)n(ws:)863 1809 y Fx(\017)41 b FC(I)989 1779 y FB(n)p FA(\002)p FB(n)1148 1809 y FG(\(or)20 b(simply)g FC(I)27 b FG(if)21 b(the)f(size)h(is)g(clear)f(from)f(the)i(conte)o 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FJ(D)q(A)t(M)t(S)g(A)t(N)t(D)h FG(H)t(.)f(J)t FJ(O)t(R)t(D)q(A)t(N)r FG(,)d Ft(Is)f(SOR)f(color)n (-blind?)p FG(,)f(SIAM)h(J.)h(Sci.)g(Statist.)g(Comput.,)f(7)g (\(1986\),)512 1994 y(pp.)g(490\226506.)374 2171 y([3])42 b(E)t(.)24 b(A)t FJ(N)t(D)t(E)t(R)t(S)t(O)t(N)t FG(,)i FJ(E)t(T)o FG(.)d FJ(A)t(L)t FG(.)r(,)d Ft(LAP)-7 b(A)n(CK)20 b(User)o(s)i(Guide)p FG(,)d(SIAM,)h(Philadelphia,)f(1992.)374 2349 y([4])42 b(J)t(.)30 b(A)t FJ(P)t(P)t(L)t(E)t(Y)l(A)t(R)t(D)g(A)t (N)t(D)g FG(I)t(.)g(C)t FJ(H)t(E)t(S)t(H)t(I)t(R)t(E)r FG(,)d Ft(Nested)f(factorization)p FG(,)g(in)f(Reserv)n(oir)g (Simulation)f(Sympo-)512 2448 y(sium)c(of)g(the)g(SPE,)h(1983.)28 b(P)o(aper)19 b(12264.)374 2626 y([5])42 b(M)t(.)20 b(A)t FJ(R)t(I)t(O)t(L)t(I)t FG(,)i(J)t(.)f(D)t FJ(E)t(M)t(M)t(E)t(L)t FG(,)f FJ(A)t(N)t(D)h FG(I)t(.)f(D)t FJ(U)t(FF)r FG(,)d Ft(Solving)d(spar)o(se)i(linear)g(systems)h(with)f(spar)o(se)h(bac)n (kwar)m(d)512 2725 y(err)l(or)p FG(,)k(SIAM)f(J.)h(Matrix)f(Anal.)g 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y(Sci.)h(Statist.)g(Comput.,)e(13)g (\(1992\),)f(pp.)i(1\22629.)374 3834 y([9])42 b(S)t(.)31 b(A)t FJ(S)t(H)t(B)t(Y)-6 b FG(,)34 b(T)n(.)d(M)t FJ(A)t(N)t(T)t(E)t(U) t(FF)t(E)t(L)t FG(,)g FJ(A)t(N)t(D)g FG(P)-5 b(.)31 b(S)t FJ(A)m(Y)t(L)t(O)t(R)r FG(,)e Ft(Adaptive)c(polynomial)g(pr)m (econditioning)e(for)512 3934 y(Hermitian)d(inde\002nite)f(linear)h (systems)p FG(,)h(BIT)-6 b(,)20 b(29)g(\(1989\),)e(pp.)h(583\226609.) 332 4111 y([10])42 b(S)t(.)22 b(F)m(.)h(A)t FJ(S)t(H)t(B)t(Y)-6 b FG(,)23 b(T)n(.)f(A)t(.)g(M)t FJ(A)t(N)t(T)t(E)t(U)t(FF)t(E)t(L)t FG(,)f FJ(A)t(N)t(D)h FG(P)-5 b(.)22 b(E)t(.)g(S)t FJ(A)m(Y)t(L)t(O)t (R)r FG(,)c Ft(A)g(taxonomy)e(for)i(conjugate)d(gr)o(adient)512 4211 y(methods)p FG(,)k(SIAM)h(J.)h(Numer)-5 b(.)20 b(Anal.,)f(27)h (\(1990\),)e(pp.)i(1542\2261568.)332 4388 y([11])42 b(C)t(.)29 b(A)t FJ(S)t(H)t(C)t(R)t(A)t(F)t(T)g(A)t(N)t(D)g FG(R)t(.)g(G)t FJ(R)t(I)t(M)t(E)t(S)r FG(,)d Ft(On)e(vectorizing)g(incomplete)e (factorizations)i(and)f(SSOR)g(pr)m(e-)512 4488 y(conditioner)o(s)p FG(,)c(SIAM)h(J.)h(Sci.)f(Statist.)i(Comput.,)c(9)j(\(1988\),)d(pp.)h (122\226151.)332 4665 y([12])42 b(O)t(.)33 b(A)t FJ(X)t(E)t(L)t(S)t(S)t (O)t(N)r FG(,)e Ft(Incomplete)c(bloc)n(k)h(matrix)h(factorization)e(pr) m(econditioning)f(methods.)h(The)i(ulti-)512 4765 y(mate)20 b(answer?)p FG(,)g(J.)h(Comput.)e(Appl.)g(Math.,)h(12&13)e(\(1985\),)g (pp.)i(3\22618.)332 4942 y([13])p 512 4929 191 4 v 231 w(,)28 b Ft(A)f(g)o(ener)o(al)f(incomplete)f(bloc)n(k-matrix)h (factorization)g(method)p FG(,)h(Linear)e(Algebra)h(Appl.,)h(74)512 5042 y(\(1986\),)18 b(pp.)h(179\226190.)332 5219 y([14])42 b(O)t(.)23 b(A)t FJ(X)t(E)t(L)t(S)t(S)t(O)t(N)g(A)t(N)t(D)g FG(A)t(.)h(B)q FJ(A)t(R)t(K)t(E)t(R)r FG(,)c Ft(F)l(inite)f(element)g (solution)f(of)g(boundary)f(value)h(pr)l(oblems.)g(The-)512 5319 y(ory)i(and)g(computation)p FG(,)d(Academic)j(Press,)g(Orlando,)f (Fl.,)h(1984.)332 5497 y([15])42 b(O)t(.)20 b(A)t FJ(X)t(E)t(L)t(S)t(S) t(O)t(N)g(A)t(N)t(D)h FG(V)-7 b(.)21 b(E)t FJ(I)t(J)t(K)t(H)t(O)t(U)t (T)r FG(,)c Ft(V)-9 b(ectorizable)15 b(pr)m(econditioner)o(s)f(for)i (elliptic)g(dif)o(fer)m(ence)f(equa-)512 5596 y(tions)20 b(in)g(thr)m(ee)h(space)f(dimensions)p FG(,)f(J.)h(Comput.)g(Appl.)f (Math.,)h(27)f(\(1989\),)f(pp.)i(299\226321.)1880 5806 y(93)p eop end %%Page: 94 104 TeXDict begin 94 103 bop 739 282 a FG(94)2561 b Fu(BIBLIOGRAPHY)780 515 y FG([16])p 960 502 191 4 v 231 w(,)25 b Ft(The)f(nested)f(r)m (ecur)o(sive)h(two-le)o(vel)g(factorization)e(method)h(for)h (nine-point)d(dif)o(fer)m(ence)i(matri-)960 615 y(ces)p FG(,)e(SIAM)f(J.)h(Sci.)f(Statist.)i(Comput.,)c(12)i(\(1991\),)e(pp.)i (1373\2261400.)780 785 y([17])42 b(O)t(.)24 b(A)t FJ(X)t(E)t(L)t(S)t(S) t(O)t(N)f(A)t(N)t(D)h FG(I)t(.)g(G)t FJ(U)t(S)t(T)n(A)t(F)t(S)t(S)t(O)t (N)r FG(,)c Ft(Iter)o(ative)e(solution)h(for)h(the)f(solution)f(of)i (the)f(Navier)h(equa-)960 885 y(tions)g(of)h(elasticity)p FG(,)f(Comput.)f(Methods)h(Appl.)f(Mech.)h(Engr)o(g.,)d(15)j(\(1978\),) e(pp.)h(241\226258.)780 1054 y([18])42 b(O)t(.)28 b(A)t FJ(X)t(E)t(L)t(S)t(S)t(O)t(N)g(A)t(N)t(D)g FG(G)t(.)g(L)t FJ(I)t(N)t(D)t(S)t(K)r(O)t(G)r FG(,)d Ft(On)f(the)f(eig)o(en)m(value)f (distrib)n(ution)h(of)h(a)f(class)h(of)g(pr)m(econdi-)960 1154 y(tioning)19 b(matrices)p FG(,)i(Numer)-5 b(.)19 b(Math.,)h(48)f(\(1986\),)f(pp.)i(479\226498.)780 1324 y([19])p 960 1311 V 231 w(,)g Ft(On)e(the)h(r)o(ate)g(of)g(con)m(ver)m (g)o(ence)d(of)j(the)g(pr)m(econditioned)d(conjugate)h(gr)o(adient)g (method)p FG(,)h(Numer)-5 b(.)960 1424 y(Math.,)20 b(48)g(\(1986\),)d (pp.)j(499\226523.)780 1594 y([20])42 b(O)t(.)34 b(A)t FJ(X)t(E)t(L)t(S)t(S)t(O)t(N)f(A)t(N)t(D)g FG(N)t(.)h(M)t FJ(U)t(N)t(K)t(S)t(G)t(A)t(A)t(R)t(D)r FG(,)e Ft(Analysis)d(of)g (incomplete)e(factorizations)h(with)i(\002xed)960 1693 y(stor)o(a)o(g)o(e)25 b(allocation)p FG(,)f(in)h(Preconditioning)d (Methods)i(\226)h(Theory)e(and)i(Applications,)f(D.)i(Ev)n(ans,)f(ed.,) 960 1793 y(Gordon)19 b(and)g(Breach,)h(Ne)n(w)g(Y)-9 b(ork,)19 b(1983,)g(pp.)g(265\226293.)780 1963 y([21])42 b(O)t(.)22 b(A)t FJ(X)t(E)t(L)t(S)t(S)t(O)t(N)f(A)t(N)t(D)h FG(B)t(.)g(P)t FJ(O)t(L)t(M)t(A)t(N)r FG(,)d Ft(On)e(appr)l(oximate)f (factorization)g(methods)g(for)i(bloc)n(k-matrices)960 2062 y(suitable)i(for)h(vector)f(and)f(par)o(allel)h(pr)l(ocessor)o(s)p FG(,)g(Linear)g(Algebra)f(Appl.,)g(77)h(\(1986\),)e(pp.)h(3\22626.)780 2232 y([22])42 b(O)t(.)23 b(A)t FJ(X)t(E)t(L)t(S)t(S)t(O)t(N)f(A)t(N)t (D)h FG(P)-5 b(.)23 b(V)-6 b FJ(A)t(S)t(S)t(I)t(L)t(E)t(V)t(S)t(K)t(I)r FG(,)19 b Ft(Alg)o(ebr)o(aic)e(multile)o(vel)h(pr)m(econditioning)e (methods,)h(I)p FG(,)i(Nu-)960 2332 y(mer)-5 b(.)20 b(Math.,)g(56)g (\(1989\),)d(pp.)j(157\226177.)780 2502 y([23])p 960 2489 V 231 w(,)i Ft(Alg)o(ebr)o(aic)e(multile)o(vel)i(pr)m (econditioning)c(methods,)i(II)p FG(,)h(SIAM)h(J.)g(Numer)-5 b(.)21 b(Anal.,)g(57)g(\(1990\),)960 2602 y(pp.)f(1569\2261590.)780 2772 y([24])42 b(O)t(.)23 b(A)t FJ(X)t(E)t(L)t(S)t(S)t(O)t(N)f(A)t(N)t (D)h FG(P)-5 b(.)22 b(S)t(.)h(V)-6 b FJ(A)t(S)t(S)t(I)t(L)t(E)t(V)t(S)t (K)t(I)r FG(,)19 b Ft(A)f(blac)n(k)g(box)f(g)o(ener)o(alized)g (conjugate)f(gr)o(adient)h(solver)960 2871 y(with)30 b(inner)g(iter)o(ations)f(and)g(variable-step)f(pr)m(econditioning)p FG(,)g(SIAM)i(J.)g(Matrix)f(Anal.)h(Appl.,)h(12)960 2971 y(\(1991\),)18 b(pp.)i(625\226644.)780 3141 y([25])42 b(R)t(.)29 b(B)q FJ(A)t(N)t(K)r FG(,)d Ft(Mar)m(c)o(hing)c(algorithms)h (for)h(elliptic)f(boundary)f(value)h(pr)l(oblems;)h(II:)f(The)h (variable)f(co-)960 3240 y(ef)o(\002cient)c(case)p FG(,)h(SIAM)h(J.)f (Numer)-5 b(.)20 b(Anal.,)g(14)f(\(1977\),)f(pp.)i(950\226970.)780 3410 y([26])42 b(R)t(.)54 b(B)q FJ(A)t(N)t(K)t FG(,)62 b(T)n(.)54 b(C)t FJ(H)t(A)t(N)t FG(,)61 b(W)l(.)55 b(C)t FJ(O)t(U)t(G)t(H)t(R)t(A)t(N)g FG(J)t FJ(R)t FG(.)t(,)61 b FJ(A)t(N)t(D)54 b FG(R)t(.)h(S)t FJ(M)t(I)t(T)t(H)r FG(,)i Ft(The)49 b(Alternate-Bloc)n(k-)960 3510 y(Factorization)41 b(pr)l(ocedur)m(e)g(for)i(systems)g(of)f(partial)g(dif)o(fer)m(ential)f (equations)p FG(,)46 b(BIT)-6 b(,)42 b(29)g(\(1989\),)960 3610 y(pp.)20 b(938\226954.)780 3780 y([27])42 b(R)t(.)25 b(B)q FJ(A)t(N)t(K)h(A)t(N)t(D)f FG(D)t(.)g(R)q FJ(O)t(S)t(E)r FG(,)c Ft(Mar)m(c)o(hing)d(algorithms)i(for)h(elliptic)f(boundary)e (value)h(pr)l(oblems.)h(I:)g(The)960 3879 y(constant)f(coef)o (\002cient)g(case)p FG(,)h(SIAM)g(J.)h(Numer)-5 b(.)19 b(Anal.,)h(14)g(\(1977\),)e(pp.)h(792\226829.)780 4049 y([28])42 b(R)t(.)28 b(E)t(.)g(B)q FJ(A)t(N)t(K)h(A)t(N)t(D)e FG(T)n(.)h(F)m(.)g(C)t FJ(H)t(A)t(N)r FG(,)d Ft(A)e(composite)f(step)i (bi-conjugate)c(gr)o(adient)i(algorithm)g(for)h(non-)960 4149 y(symmetric)i(linear)f(systems)p FG(,)i(T)-6 b(ech.)24 b(Rep.)g(CAM)g(92-,)g(UCLA,)h(Dept.)f(of)f(Math.,)i(Los)f(Angeles,)g (CA)960 4248 y(90024-1555,)16 b(1992.)780 4418 y([29])42 b(R)t(.)36 b(E)t(.)g(B)q FJ(A)t(N)t(K)h(A)t(N)t(D)f FG(T)n(.)f(F)m(.)h (C)t FJ(H)t(A)t(N)r FG(,)f Ft(An)c(analysis)g(of)g(the)h(composite)e (step)i(Biconjugate)d(gr)o(adient)960 4518 y(method)p FG(,)19 b(Numerische)g(Mathematik,)g(66)h(\(1993\),)d(pp.)j (295\226319.)780 4688 y([30])42 b(G)t(.)22 b(B)q FJ(AU)t(D)t(E)t(T)r FG(,)c Ft(Async)o(hr)l(onous)d(iter)o(ative)i(methods)f(for)i(multipr)l (ocessor)o(s)p FG(,)g(J.)f(Assoc.)g(Comput.)f(Mach.,)960 4788 y(25)k(\(1978\),)e(pp.)h(226\226244.)780 4957 y([31])42 b(R)t(.)33 b(B)t FJ(E)t(AU)t(W)t(E)t(N)t(S)r FG(,)c Ft(On)f(Axelsson')m (s)e(perturbations)p FG(,)i(Linear)f(Algebra)f(Appl.,)i(68)f(\(1985\),) g(pp.)g(221\226)960 5057 y(242.)780 5227 y([32])p 960 5214 V 231 w(,)20 b Ft(Appr)l(oximate)e(factorizations)h(with)h(S/P)f (consistently)g(or)m(der)m(ed)f FC(M)9 b Ft(-factor)o(s)p FG(,)19 b(BIT)-6 b(,)20 b(29)f(\(1989\),)960 5327 y(pp.)h(658\226681.) 780 5497 y([33])42 b(R)t(.)36 b(B)t FJ(E)t(AU)t(W)t(E)t(N)t(S)f(A)t(N)t (D)h FG(L)t(.)f(Q)s FJ(U)t(E)t(N)t(O)t(N)r FG(,)f Ft(Existence)c (criteria)i(for)f(partial)f(matrix)h(factorizations)f(in)960 5596 y(iter)o(ative)20 b(methods)p FG(,)g(SIAM)g(J.)h(Numer)-5 b(.)19 b(Anal.,)h(13)g(\(1976\),)e(pp.)h(615\226643.)p eop end %%Page: 95 105 TeXDict begin 95 104 bop 291 282 a Fu(BIBLIOGRAPHY)2561 b FG(95)332 515 y([34])42 b(A)t(.)e(B)t FJ(J)738 508 y FG(\250)728 515 y FJ(O)t(R)t(C)t(K)i(A)t(N)t(D)f FG(T)n(.)f(E)t FJ(L)t(F)t(V)t(I)t(N)t(G)r FG(,)g Ft(Acceler)o(ated)35 b(pr)l(ojection)g(methods)g(for)h(computing)e(pseudo-)512 615 y(in)m(ver)o(se)20 b(solutions)g(of)g(systems)i(of)e(linear)g (equations)p FG(,)e(BIT)-6 b(,)21 b(19)e(\(1979\),)f(pp.)i(145\226163.) 332 789 y([35])42 b(D)t(.)20 b(B)t FJ(R)t(A)t(E)t(S)t(S)r FG(,)e Ft(The)e(contr)o(action)e(number)h(of)h(a)f(multigrid)h(method)f (for)h(solving)f(the)h(Poisson)f(equation)p FG(,)512 889 y(Numer)-5 b(.)19 b(Math.,)h(37)g(\(1981\),)e(pp.)h(387\226404.)332 1063 y([36])42 b(J)t(.)24 b(H)t(.)g(B)t FJ(R)t(A)t(M)t(B)t(L)t(E)t FG(,)h(J)t(.)f(E)t(.)f(P)m FJ(A)t(S)t(C)t(I)t(A)t(K)t FG(,)j FJ(A)t(N)t(D)e FG(A)t(.)f(H)t(.)h(S)t FJ(C)t(H)t(A)m(T)t(Z)r FG(,)c 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b(Proceedings)23 b(of)h(the)g(Second)f(International)f(Symposium)512 4675 y(on)e(Domain)f(Decomposition)f(Methods,)h(Los)h(Angeles,)g(CA,)h (January)e(14)h(-)g(16,)f(1988.)332 4849 y([48])p 512 4836 V 231 w(,)e(eds.,)f Ft(Domain)f(Decomposition)g(Methods)p FG(,)h(Philadelphia,)f(1990,)g(SIAM.)20 b(Proceedings)14 b(of)i(the)512 4949 y(Third)j(International)f(Symposium)h(on)g(Domain)h (Decomposition)e(Methods,)h(Houston,)g(TX,)h(1989.)332 5123 y([49])p 512 5110 V 231 w(,)28 b(eds.,)g Ft(Domain)e (Decomposition)f(Methods)p FG(,)j(SIAM,)e(Philadelphia,)h(1991.)48 b(Proceedings)25 b(of)512 5223 y(the)d(Fourth)e(International)g (Symposium)g(on)h(Domain)g(Decomposition)e(Methods,)i(Mosco)n(w)-5 b(,)21 b(USSR,)512 5322 y(1990.)332 5497 y([50])42 b(T)n(.)23 b(C)t FJ(H)t(A)t(N)g(A)t(N)t(D)g FG(C)t(.)t(-)t(C)t(.)h(J)t(.)f(K)t FJ(U)t(O)r FG(,)d Ft(T)-6 b(wo-color)18 b(Fourier)g(analysis)g(of)h (iter)o(ative)f(algorithms)g(for)h(elliptic)512 5596 y(pr)l(oblems)h(with)h(r)m(ed/blac)n(k)e(or)m(dering)p FG(,)g(SIAM)i(J.)f(Sci.)h(Statist.)g(Comput.,)e(11)h(\(1990\),)e(pp.)h (767\226793.)p eop end %%Page: 96 106 TeXDict begin 96 105 bop 739 282 a FG(96)2561 b Fu(BIBLIOGRAPHY)780 515 y FG([51])42 b(T)n(.)23 b(F)m(.)h(C)t FJ(H)t(A)t(N)t FG(,)g(T)n(.)f(P)-5 b(.)24 b(M)t FJ(A)m(T)t(H)t(E)t(W)m FG(,)e FJ(A)t(N)t(D)i FG(J)t(.)f(P)-5 b(.)24 b(S)t FJ(H)t(AO)r FG(,)c Ft(Ef)o(\002cient)e(variants)g(of)h(the)g(verte)n(x)g(space)g (domain)960 615 y(decomposition)d(algorithm)p FG(,)h(T)-6 b(ech.)17 b(Rep.)h(CAM)h(92-07,)d(UCLA,)i(Dept.)g(of)f(Math.,)h(Los)g (Angeles,)f(CA)960 715 y(90024-1555,)f(1992.)28 b(SIAM)20 b(J.)h(Sci.)f(Comput.,)f(to)i(appear)-5 b(.)780 883 y([52])42 b(T)n(.)36 b(F)m(.)g(C)t FJ(H)t(A)t(N)g(A)t(N)t(D)g FG(J)t(.)g(S)t FJ(H)t(AO)r FG(,)f Ft(On)c(the)g(c)o(hoice)g(of)g(coar)o(se)g(grid)g (size)h(in)g(domain)d(decomposition)960 982 y(methods)p FG(,)19 b(tech.)h(rep.,)g(UCLA,)g(Dept.)g(of)g(Math.,)f(Los)i(Angeles,) 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b(Delft,)j(The)g(Netherlands,)f(1991.)780 4426 y([63])42 b(E)t(.)23 b(D)t FJ(E)g FG(S)t FJ(T)t(U)t(R)t(L)t(E)t(R)g(A)t(N)t(D)h FG(D)t(.)f(R)t(.)g(F)t FJ(O)t(K)t(K)t(E)t(M)t(A)r FG(,)d Ft(Nested)f(Krylo)o(v)g(methods)f(and)g(pr)m(eserving)g(the)g(ortho)o (g-)960 4525 y(onality)p FG(,)h(T)-6 b(ech.)20 b(Rep.)g(Preprint)g (796,)f(Utrecht)g(Uni)n(v)o(ersity)-5 b(,)19 b(Utrecht,)g(The)h (Netherlands,)f(1993.)780 4693 y([64])42 b(S)t(.)28 b(D)t FJ(E)t(M)t(K)r(O)t FG(,)g(W)l(.)h(M)t FJ(O)t(S)t(S)t FG(,)f FJ(A)t(N)t(D)f FG(P)-5 b(.)28 b(S)t FJ(M)t(I)t(T)t(H)r FG(,)c Ft(Decay)f(r)o(ates)g(for)h(in)m(ver)o(ses)f(of)g(band)f (matrices)p FG(,)i(Mathe-)960 4793 y(matics)d(of)f(Computation,)e(43)i (\(1984\),)d(pp.)j(491\226499.)780 4961 y([65])42 b(J)t(.)30 b(D)t FJ(E)t(M)t(M)t(E)t(L)r FG(,)d Ft(The)e(condition)e(number)i(of)g (equivalence)e(tr)o(ansformations)h(that)h(bloc)n(k)g(dia)o(gonalize) 960 5061 y(matrix)c(pencils)p FG(,)e(SIAM)i(J.)g(Numer)-5 b(.)19 b(Anal.,)h(20)g(\(1983\),)d(pp.)j(599\226610.)780 5229 y([66])42 b(J)t(.)30 b(D)t FJ(E)t(M)t(M)t(E)t(L)t FG(,)f(M)t(.)h(H)t FJ(E)t(A)m(T)t(H)t FG(,)f FJ(A)t(N)t(D)g FG(H)t(.)g FJ(V)-5 b(A)t(N)30 b(D)t(E)t(R)f FG(V)q FJ(O)t(R)t(S)t(T)r FG(,)e Ft(P)-7 b(ar)o(allel)24 b(linear)h(alg)o(ebr)o(a)p FG(,)f(in)h(Acta)g(Nu-)960 5328 y(merica,)20 b(V)-11 b(ol.)20 b(2,)g(Cambridge)f(Press,)h(Ne)n(w)h(Y)-9 b(ork,)19 b(1993.)780 5497 y([67])42 b(S)t(.)35 b(D)t FJ(O)t(I)r FG(,)e Ft(On)d(par)o(allelism)g(and)f(con)m(ver)m(g)o(ence)f(of)i (incomplete)f(LU)i(factorizations)p FG(,)g(Appl.)f(Numer)-5 b(.)960 5596 y(Math.,)20 b(7)g(\(1991\),)e(pp.)h(417\226436.)p eop end %%Page: 97 107 TeXDict begin 97 106 bop 291 282 a Fu(BIBLIOGRAPHY)2561 b FG(97)332 515 y([68])42 b(J)t(.)22 b(D)t FJ(O)t(N)t(G)t(A)t(R)t(R)t (A)t FG(,)i(J)t(.)e(D)t FJ(U)t FG(C)t FJ(R)q(O)t(Z)t FG(,)i(I)t(.)e(D)t FJ(U)t(FF)t FG(,)g FJ(A)t(N)t(D)h FG(S)t(.)f(H)t FJ(A)t(M)t(M)t(A)t(R)t(L)t(I)t(N)t(G)r FG(,)d Ft(A)f(set)h(of)e(le)o(vel)h(3)f(Basic)h(Linear)512 615 y(Alg)o(ebr)o(a)h(Subpr)l(o)o(gr)o(ams)p FG(,)f(A)m(CM)j(T)m(rans.) e(Math.)h(Soft.,)g(16)g(\(1990\),)d(pp.)j(1\22617.)332 785 y([69])42 b(J)t(.)36 b(D)t FJ(O)t(N)t(G)t(A)t(R)t(R)t(A)t FG(,)k(J)t(.)c(D)t FJ(U)t FG(C)t FJ(R)q(O)t(Z)t FG(,)k(S)t(.)c(H)t FJ(A)t(M)t(M)t(A)t(R)t(L)t(I)t(N)t(G)t FG(,)k FJ(A)t(N)t(D)c FG(R)t(.)g(H)t FJ(A)t(N)t(S)t(O)t(N)r FG(,)f Ft(An)c(e)n(xtended)g(set) h(of)512 885 y(FORTRAN)21 b(Basic)g(Linear)h(Alg)o(ebr)o(a)e(Subpr)l(o) o(gr)o(ams)p FG(,)f(A)m(CM)j(T)m(rans.)f(Math.)g(Soft.,)g(14)g (\(1988\),)e(pp.)h(1\226)512 984 y(32.)332 1154 y([70])42 b(J)t(.)21 b(D)t FJ(O)t(N)t(G)t(A)t(R)t(R)t(A)t FG(,)i(I)t(.)d(D)t FJ(U)t(FF)t FG(,)h(D)t(.)g(S)t FJ(O)t(R)t(E)t(N)t(S)t(E)t(N)t FG(,)h FJ(A)t(N)t(D)f FG(H)t(.)f FJ(V)-5 b(A)t(N)21 b(D)t(E)t(R)g FG(V)q FJ(O)t(R)t(S)t(T)r FG(,)d Ft(Solving)c(Linear)i(Systems)512 1254 y(on)k(V)-9 b(ector)20 b(and)f(Shar)m(ed)g(Memory)h(Computer)o(s)p FG(,)g(SIAM,)g(Philadelphia,)f(P)-8 b(A,)21 b(1991.)332 1424 y([71])42 b(J)t(.)23 b(D)t FJ(O)t(N)t(G)t(A)t(R)t(R)t(A)i(A)t(N)t (D)e FG(E)t(.)g(G)t FJ(R)q(O)t(S)t(S)t(E)r FG(,)d Ft(Distrib)n(ution)f (of)f(mathematical)g(softwar)m(e)h(via)f(electr)l(onic)h(mail)p FG(,)512 1523 y(Comm.)g(A)m(CM,)i(30)f(\(1987\),)d(pp.)j(403\226407.) 332 1693 y([72])42 b(J)t(.)20 b(D)t FJ(O)t(N)t(G)t(A)t(R)t(R)t(A)t FG(,)i(C)t(.)f(M)t FJ(O)t(L)t(E)t(R)t FG(,)g(J)t(.)f(B)s FJ(U)t(N)t(C)t(H)t FG(,)i FJ(A)t(N)t(D)f FG(G)t(.)f(S)t FJ(T)t(E)t(W)l(A)t(RT)r FG(,)c Ft(LINP)-7 b(A)n(CK)16 b(User)o(s')g(Guide)p FG(,)g(SIAM,)512 1793 y(Philadelphia,)j(1979.)332 1963 y([73])42 b(J)t(.)30 b(D)t FJ(O)t(N)t(G)t(A)t(R)t(R)t(A)h(A)t(N)t (D)f FG(H)t(.)g(V)-6 b FJ(A)t(N)30 b(D)t(E)t(R)g FG(V)q FJ(O)t(R)t(S)t(T)r FG(,)d Ft(P)-7 b(erformance)24 b(of)i(various)f (computer)o(s)g(using)f(stan-)512 2062 y(dar)m(d)18 b(spar)o(se)i (linear)f(equations)f(solving)g(tec)o(hniques)p FG(,)g(in)h(Computer)f (Benchmarks,)g(J.)i(Dongarra)c(and)512 2162 y(W)-8 b(.)21 b(Gentzsch,)f(eds.,)g(Else)n(vier)f(Science)h(Publishers)g(B.V)-11 b(.,)21 b(Ne)n(w)f(Y)-9 b(ork,)19 b(1993,)g(pp.)g(177\226188.)332 2332 y([74])42 b(F)m(.)29 b(D)t FJ(O)t(R)t(R)r FG(,)d Ft(The)e(dir)m(ect)h(solution)e(of)h(the)g(discr)m(ete)g(Poisson)g (equation)e(on)i(a)g(r)m(ectangle)p FG(,)f(SIAM)i(Re)n(v)-5 b(.,)512 2432 y(12)20 b(\(1970\),)e(pp.)h(248\226263.)332 2602 y([75])42 b(M)t(.)23 b(D)t FJ(RY)t(JA)h(A)t(N)t(D)g FG(O)t(.)g(B)t(.)g(W)t FJ(I)t(D)t(L)t(U)t(N)t(D)r FG(,)c Ft(T)-8 b(owar)m(ds)20 b(a)f(uni\002ed)e(theory)i(of)g(domain)f (decomposition)f(algo-)512 2701 y(rithms)26 b(for)f(elliptic)g(pr)l (oblems)p FG(,)h(T)-6 b(ech.)24 b(Rep.)h(486,)g(also)g(Ultracomputer)e (Note)i(167,)g(Department)e(of)512 2801 y(Computer)c(Science,)g (Courant)h(Institute,)f(1989.)332 2971 y([76])42 b(D)t(.)26 b(D)t FJ(U)t(B)t(O)t(I)t(S)t FG(,)g(A)t(.)g(G)t FJ(R)t(E)t(E)t(N)t(B)r (AU)t(M)t FG(,)h FJ(A)t(N)t(D)f FG(G)t(.)f(R)q FJ(O)t(D)t(R)t(I)t(G)t (U)t(E)r FG(,)e Ft(Appr)l(oximating)c(the)j(in)m(ver)o(se)f(of)g(a)h (matrix)512 3070 y(for)f(use)f(in)g(iter)o(ative)h(algorithms)e(on)h (vector)g(pr)l(ocessor)o(s)p FG(,)h(Computing,)d(22)i(\(1979\),)e(pp.)h (257\226268.)332 3240 y([77])42 b(I)t(.)21 b(D)t FJ(U)t(FF)t FG(,)h(R)t(.)g(G)t FJ(R)t(I)t(M)t(E)t(S)t FG(,)g FJ(A)t(N)t(D)g FG(J)t(.)f(L)t FJ(E)t(W)t(I)t(S)r FG(,)d Ft(Spar)o(se)e(matrix)h(test)h (pr)l(oblems)p FG(,)f(A)m(CM)g(T)m(rans.)f(Math.)g(Soft.,)512 3340 y(15)k(\(1989\),)e(pp.)h(1\22614.)332 3510 y([78])42 b(I)t(.)25 b(D)t FJ(U)t(FF)g(A)t(N)t(D)g FG(G)t(.)h(M)t FJ(E)t(U)t(R)t(A)t(N)t(T)r FG(,)21 b Ft(The)f(ef)o(fect)h(of)g(or)m (dering)e(on)i(pr)m(econditioned)d(conjugate)g(gr)o(adients)p FG(,)512 3610 y(BIT)-6 b(,)20 b(29)g(\(1989\),)e(pp.)h(635\226657.)332 3780 y([79])42 b(I)t(.)25 b(S)t(.)h(D)t FJ(U)t(FF)t FG(,)g(A)t(.)f(M)t (.)h(E)t FJ(R)t(I)t(S)t(M)t(A)t(N)t FG(,)g FJ(A)t(N)t(D)g FG(J)t(.)t(K)t(.)t(R)t FJ(E)t(I)t(D)r FG(,)c Ft(Dir)m(ect)g(methods)e (for)i(spar)o(se)f(matrices)p FG(,)h(Oxford)512 3879 y(Uni)n(v)o(ersity)d(Press,)i(London,)c(1986.)332 4049 y([80])42 b(T)n(.)d(D)t FJ(U)t(P)t(O)t(N)t(T)o FG(,)k(R)t(.)d(K)t FJ(E)t(N)t(D)q(A)t(L)t(L)t FG(,)j FJ(A)t(N)t(D)c FG(H)t(.)h(R)t FJ(A)q(C)t(H)t(F)t(O)t(R)t(D)r FG(,)h Ft(An)35 b(appr)l(oximate)e (factorization)h(pr)l(oce-)512 4149 y(dur)m(e)22 b(for)i(solving)e (self-adjoint)f(elliptic)i(dif)o(fer)m(ence)f(equations)p FG(,)g(SIAM)h(J.)g(Numer)-5 b(.)22 b(Anal.,)h(5)g(\(1968\),)512 4248 y(pp.)c(559\226573.)332 4418 y([81])42 b(E)t(.)31 b(D)t(')t(Y)-5 b FJ(A)t(K)r(O)t(N)t(O)q(V)r FG(,)28 b Ft(The)f(method)f(of)g(variable)g(dir)m(ections)g(in)h(solving)f (systems)i(of)f(\002nite)f(dif)o(fer)m(ence)512 4518 y(equations)p FG(,)18 b(So)o(viet)i(Math.)g(Dokl.,)f(2)h(\(1961\),)e (pp.)i(577\226580.)26 b(T)o(OM)20 b(138,)f(271\226274.)332 4688 y([82])42 b(L)t(.)24 b(E)t FJ(H)t(R)t(L)t(I)t(C)t(H)r FG(,)e Ft(An)e(Ad-Hoc)f(SOR)h(method)p FG(,)e(J.)j(Comput.)e(Phys.,)h (43)f(\(1981\),)f(pp.)i(31\22645.)332 4858 y([83])42 b(M)t(.)21 b(E)t FJ(I)t(E)t(R)t(M)t(A)t(N)t(N)h(A)t(N)t(D)g FG(R)t(.)g(V)-6 b FJ(A)t(R)t(G)t(A)r FG(,)18 b Ft(Is)g(the)e(optimal)h FC(!)j Ft(best)d(for)g(the)g(SOR)g(iter)o(ation)f(method?)p FG(,)g(Linear)512 4957 y(Algebra)j(Appl.,)g(182)h(\(1993\),)e(pp.)h (257\226277.)332 5127 y([84])42 b(V)-7 b(.)31 b(E)t FJ(I)t(J)t(K)t(H)t (O)t(U)t(T)r FG(,)c Ft(Analysis)f(of)g(par)o(allel)f(incomplete)g (point)g(factorizations)p FG(,)h(Linear)f(Algebra)g(Appl.,)512 5227 y(154\226156)17 b(\(1991\),)h(pp.)i(723\226740.)332 5397 y([85])p 512 5384 191 4 v 231 w(,)28 b Ft(Be)o(war)m(e)d(of)h (unperturbed)e(modi\002ed)h(incomplete)f(point)i(factorizations)p FG(,)g(in)g(Proceedings)e(of)512 5497 y(the)17 b(IMA)m(CS)h (International)d(Symposium)h(on)g(Iterati)n(v)o(e)h(Methods)f(in)i (Linear)e(Algebra,)h(Brussels,)h(Bel-)512 5596 y(gium,)h(R.)i(Beauwens) f(and)g(P)-9 b(.)20 b(de)g(Groen,)f(eds.,)h(1992.)p eop end %%Page: 98 108 TeXDict begin 98 107 bop 739 282 a FG(98)2561 b Fu(BIBLIOGRAPHY)780 515 y FG([86])p 960 502 191 4 v 231 w(,)36 b Ft(LAP)-7 b(A)n(CK)32 b(working)h(note)f(50:)49 b(Distrib)n(uted)32 b(spar)o(se)h(data)f(structur)m(es)h(for)g(linear)f(alg)o(ebr)o(a)960 615 y(oper)o(ations)p FG(,)17 b(T)-6 b(ech.)19 b(Rep.)f(CS)i(92-169,)d (Computer)g(Science)i(Department,)e(Uni)n(v)o(ersity)g(of)i(T)-6 b(ennessee,)960 715 y(Knoxville,)19 b(TN,)h(1992.)780 879 y([87])p 960 866 V 231 w(,)d Ft(LAP)-7 b(A)n(CK)15 b(working)h(note)f(51:)22 b(Qualitative)14 b(pr)l(operties)i(of)g(the)f (conjugate)f(gr)o(adient)g(and)h(Lanc-)960 978 y(zos)22 b(methods)f(in)g(a)g(matrix)h(fr)o(ame)o(work)p FG(,)f(T)-6 b(ech.)21 b(Rep.)g(CS)h(92-170,)d(Computer)h(Science)h(Department,)960 1078 y(Uni)n(v)o(ersity)e(of)h(T)-6 b(ennessee,)20 b(Knoxville,)e(TN,)i (1992.)780 1242 y([88])42 b(V)-7 b(.)32 b(E)t FJ(I)t(J)t(K)t(H)t(O)t(U) t(T)g(A)t(N)t(D)h FG(B)t(.)f(P)t FJ(O)t(L)t(M)t(A)t(N)r FG(,)e Ft(Decay)d(r)o(ates)g(of)h(in)m(ver)o(ses)g(of)f(banded)f FC(M)9 b Ft(-matrices)27 b(that)g(ar)m(e)960 1342 y(near)20 b(to)h(Toeplitz)f(matrices)p FG(,)g(Linear)g(Algebra)f(Appl.,)g(109)g (\(1988\),)f(pp.)i(247\226277.)780 1506 y([89])42 b(V)-7 b(.)32 b(E)t FJ(I)t(J)t(K)t(H)t(O)t(U)t(T)g(A)t(N)t(D)f FG(P)-5 b(.)32 b(V)-6 b FJ(A)t(S)t(S)t(I)t(L)t(E)t(V)t(S)t(K)t(I)r FG(,)29 b Ft(P)-7 b(ositive)27 b(de\002nitess)g(aspects)g(of)g (vectorizable)f(pr)m(econdi-)960 1605 y(tioner)o(s)p FG(,)21 b(P)o(arallel)f(Computing,)e(10)i(\(1989\),)d(pp.)j(93\226100.) 780 1769 y([90])42 b(S)t(.)36 b(E)t FJ(I)t(S)t(E)t(N)t(S)t(T)n(A)m(T)r FG(,)e Ft(Ef)o(\002cient)c(implementation)f(of)j(a)f(class)h(of)g(pr)m (econditioned)c(conjugate)i(gr)o(adient)960 1869 y(methods)p FG(,)19 b(SIAM)i(J.)g(Sci.)f(Statist.)h(Comput.,)e(2)h(\(1981\),)e(pp.) i(1\2264.)780 2033 y([91])42 b(R)t(.)e(E)t FJ(L)t(K)t(I)t(N)r FG(,)g Ft(Con)m(ver)m(g)o(ence)33 b(theor)m(ems)i(for)h(Gauss-Seidel)d (and)i(other)g(minimization)f(algorithms)p FG(,)960 2133 y(T)-6 b(ech.)27 b(Rep.)h(68-59,)g(Computer)e(Science)i(Center)m(,)h (Uni)n(v)o(ersity)e(of)g(Maryland,)h(Colle)o(ge)f(P)o(ark,)i(MD,)960 2232 y(Jan.)20 b(1968.)780 2396 y([92])42 b(H)t(.)24 b(E)t FJ(L)t(M)t(A)t(N)r FG(,)19 b Ft(Appr)l(oximate)e(Sc)o(hur)h (complement)g(pr)m(econditioner)o(s)f(on)h(serial)i(and)e(par)o(allel)g (comput-)960 2496 y(er)o(s)p FG(,)j(SIAM)g(J.)f(Sci.)h(Statist.)g (Comput.,)e(10)h(\(1989\),)e(pp.)h(581\226605.)780 2660 y([93])42 b(H)t(.)27 b(E)t FJ(L)t(M)t(A)t(N)g(A)t(N)t(D)f FG(M)t(.)h(S)t FJ(C)t(H)t(U)t(L)n(T)t(Z)r FG(,)c Ft(Pr)m(econditioning) c(by)j(fast)h(dir)m(ect)f(methods)g(for)g(non)f(self-adjoint)960 2760 y(nonsepar)o(able)d(elliptic)i(equations)p FG(,)e(SIAM)j(J.)g (Numer)-5 b(.)19 b(Anal.,)h(23)g(\(1986\),)d(pp.)j(44\22657.)780 2924 y([94])42 b(L)t(.)22 b(E)t FJ(L)t(S)t(N)t(E)t(R)r FG(,)17 b Ft(A)h(note)e(on)h(optimal)f(bloc)n(k-scaling)g(of)h (matrices)p FG(,)h(Numer)-5 b(.)16 b(Math.,)h(44)g(\(1984\),)e(pp.)i (127\226)960 3024 y(128.)780 3188 y([95])42 b(V)-7 b(.)25 b(F)o FJ(A)t(B)t(E)t(R)g(A)t(N)t(D)g FG(T)n(.)f(M)t FJ(A)t(N)t(T)t(E)t (U)t(FF)t(E)t(L)r FG(,)19 b Ft(Necessary)h(and)f(suf)o(\002cient)g (conditions)g(for)h(the)g(e)n(xistence)g(of)g(a)960 3287 y(conjugate)e(gr)o(adient)h(method)p FG(,)g(SIAM)i(J.)f(Numer)-5 b(.)20 b(Anal.,)f(21)h(\(1984\),)e(pp.)i(315\226339.)780 3451 y([96])42 b(G)t(.)c(F)o FJ(A)t(I)t(RW)t(E)t(A)m(T)t(H)t(E)t(R)t FG(,)i(A)t(.)d(G)t FJ(O)t(U)t(R)t(L)t(A)m(Y)-6 b FG(,)42 b FJ(A)t(N)t(D)37 b FG(A)t(.)h(M)t FJ(I)t(T)t(C)t(H)t(E)t(L)t(L)r FG(,)d Ft(Some)e(high)f(accur)o(acy)f(dif)o(fer)m(ence)960 3551 y(sc)o(hemes)18 b(with)g(a)g(splitting)f(oper)o(ator)f(for)i (equations)e(of)i(par)o(abolic)e(and)h(elliptic)g(type)p FG(,)h(Numer)-5 b(.)17 b(Math.,)960 3651 y(10)j(\(1967\),)e(pp.)h (56\22666.)780 3815 y([97])42 b(R)t(.)31 b(F)t FJ(L)t(E)t(T)t(C)t(H)t (E)t(R)r FG(,)d Ft(Conjugate)d(gr)o(adient)g(methods)g(for)h (inde\002nite)f(systems)p FG(,)k(in)d(Numerical)f(Analysis)960 3914 y(Dundee)19 b(1975,)g(G.)h(W)-7 b(atson,)21 b(ed.,)e(Berlin,)h(Ne) n(w)h(Y)-9 b(ork,)19 b(1976,)f(Springer)h(V)-9 b(erlag,)19 b(pp.)h(73\22689.)780 4078 y([98])42 b(G)t(.)25 b(F)t FJ(O)t(R)t(S)t(Y)t(T)t(H)t(E)g(A)t(N)t(D)g FG(E)t(.)f(S)t FJ(T)t(R)t(AU)t(S)t(S)r FG(,)d Ft(On)g(best)f(conditioned)e(matrices)p FG(,)i(Proc.)g(Amer)-5 b(.)20 b(Math.)f(Soc.,)h(6)960 4178 y(\(1955\),)e(pp.)i(340\226345.)780 4342 y([99])42 b(R)t(.)31 b(F)t FJ(R)t(E)t(U)t(N)t(D)r FG(,)c Ft(Conjugate)d(gr)o (adient-type)f(methods)h(for)i(linear)f(systems)i(with)f(comple)n(x)e (symmetric)960 4442 y(coef)o(\002cient)19 b(matrices)p FG(,)h(SIAM)g(J.)h(Sci.)g(Statist.)g(Comput.,)e(13)h(\(1992\),)d(pp.)j (425\226448.)739 4606 y([100])41 b(R)t(.)24 b(F)t FJ(R)t(E)t(U)t(N)t(D) t FG(,)f(M)t(.)g(G)t FJ(U)t(T)t(K)t(N)t(E)t(C)t(H)t(T)o FG(,)g FJ(A)t(N)t(D)g FG(N)t(.)g(N)q FJ(A)q(C)t(H)t(T)t(I)t(G)t(A)t(L)r FG(,)d Ft(An)e(implementation)f(of)i(the)f(look-ahead)960 4705 y(Lanczos)i(algorithm)g(for)h(non-Hermitian)e(matrices)p FG(,)h(SIAM)h(J.)g(Sci.)g(Comput.,)e(14)h(\(1993\),)f(pp.)h(137\226)960 4805 y(158.)739 4969 y([101])41 b(R)t(.)46 b(F)t FJ(R)t(E)t(U)t(N)t(D)g (A)t(N)t(D)f FG(N)t(.)h(N)q FJ(A)q(C)t(H)t(T)t(I)t(G)t(A)t(L)r FG(,)h Ft(QMR:)41 b(A)g(quasi-minimal)e(r)m(esidual)h(method)g(for)h (non-)960 5069 y(Hermitian)20 b(linear)g(systems)p FG(,)i(Numer)-5 b(.)19 b(Math.,)h(60)f(\(1991\),)f(pp.)i(315\226339.)739 5233 y([102])p 960 5220 V 230 w(,)d Ft(An)f(implementation)e(of)i(the)g (QMR)g(method)f(based)g(on)h(coupled)e(two-term)i(r)m(ecurr)m(ences)p FG(,)h(T)-6 b(ech.)960 5333 y(Rep.)20 b(92.15,)f(RIA)m(CS,)h(N)m(ASA)h (Ames,)g(Ames,)f(CA,)h(1992.)739 5497 y([103])41 b(R)t(.)22 b(F)t FJ(R)t(E)t(U)t(N)t(D)g(A)t(N)t(D)f FG(T)n(.)g(S)t FJ(Z)t(E)t(T)s(O)r FG(,)c Ft(A)g(quasi-minimal)d(r)m(esidual)j(squar)m (ed)e(algorithm)h(for)h(non-Hermitian)960 5596 y(linear)j(systems)p FG(,)h(tech.)f(rep.,)g(RIA)m(CS,)g(N)m(ASA)h(Ames,)f(Ames,)g(CA,)h (1991.)p eop end %%Page: 99 109 TeXDict begin 99 108 bop 291 282 a Fu(BIBLIOGRAPHY)2561 b FG(99)291 515 y([104])41 b(R)t(.)24 b(W)l(.)f(F)t FJ(R)t(E)t(U)t(N)t (D)r FG(,)d Ft(A)f(tr)o(anspose-fr)m(ee)f(quasi-minimum)e(r)m(esidual)j (algorithm)e(for)i(non-Hermitian)e(lin-)512 615 y(ear)j(systems)p FG(,)h(SIAM)g(J.)g(Sci.)f(Comput.,)f(14)h(\(1993\),)e(pp.)h (470\226482.)291 787 y([105])41 b(R)t(.)28 b(W)l(.)g(F)t FJ(R)t(E)t(U)t(N)t(D)t FG(,)g(G)t(.)g(H)t(.)f(G)t FJ(O)t(L)t(U)t(B)t FG(,)h FJ(A)t(N)t(D)g FG(N)t(.)f(M)t(.)g(N)q FJ(A)q(C)t(H)t(T)t(I)t(G)t (A)t(L)r FG(,)e Ft(Iter)o(ative)e(solution)f(of)h(linear)f(sys-)512 886 y(tems)p FG(,)f(Acta)f(Numerica,)f(\(1992\),)f(pp.)h(57\226100.)291 1058 y([106])41 b(R)t(.)22 b(G)t FJ(L)t(O)r(W)t(I)t(N)t(S)t(K)t(I)t FG(,)g(G)t(.)g(H)t(.)g(G)t FJ(O)t(L)t(U)t(B)t FG(,)g(G)t(.)g(A)t(.)f(M) t FJ(E)t(U)t(R)t(A)t(N)t(T)o FG(,)h FJ(A)t(N)t(D)g FG(J)t(.)g(P)2532 1051 y(\264)2526 1058 y FJ(E)t(R)t(I)t(AU)t(X)r FG(,)d(eds.,)e Ft(Domain)g(Decom-)512 1157 y(position)f(Methods)h(for)g(P)-7 b(artial)17 b(Dif)o(fer)m(ential)g(Equations)p FG(,)f(SIAM,)h (Philadelphia,)f(1988.)21 b(Proceedings)512 1257 y(of)d(the)h(First)g (International)d(Symposium)h(on)h(Domain)g(Decomposition)e(Methods)i (for)g(P)o(artial)h(Dif)n(fer)n(-)512 1357 y(ential)h(Equations,)f(P)o (aris,)h(France,)f(January)g(1987.)291 1528 y([107])41 b(G)t(.)28 b(G)t FJ(O)t(L)t(U)t(B)g(A)t(N)t(D)g FG(D)t(.)g(O)t(')t(L)t FJ(E)t(A)t(RY)r FG(,)c Ft(Some)f(history)g(of)h(the)f(conjugate)f(gr)o (adient)g(and)g(Lanczos)h(meth-)512 1628 y(ods)p FG(,)d(SIAM)g(Re)n(v) -5 b(.,)20 b(31)f(\(1989\),)f(pp.)i(50\226102.)291 1799 y([108])41 b(G)t(.)26 b(G)t FJ(O)t(L)t(U)t(B)h(A)t(N)t(D)f FG(C)t(.)h(V)-6 b FJ(A)t(N)26 b FG(L)t FJ(O)r(A)t(N)r FG(,)d Ft(Matrix)f(Computations,)e FG(second)h(edition,)g(The)h(Johns)f (Hopkins)512 1899 y(Uni)n(v)o(ersity)e(Press,)i(Baltimore,)e(1989.)291 2071 y([109])41 b(A)t(.)22 b(G)t FJ(R)t(E)t(E)t(N)t(B)r(AU)t(M)h(A)t(N) t(D)f FG(Z)t(.)f(S)t FJ(T)t(R)t(A)t(K)r(O)t(S)r FG(,)e Ft(Pr)m(edicting)e(the)g(behavior)f(of)i(\002nite)f(pr)m(ecision)g (Lanczos)g(and)512 2170 y(conjugate)h(gr)o(adient)h(computations)p FG(,)f(SIAM)i(J.)h(Mat.)f(Anal.)g(Appl.,)f(13)h(\(1992\),)e(pp.)i (121\226137.)291 2342 y([110])41 b(W)l(.)21 b(D)t(.)f(G)t FJ(R)q(O)t(P)t(P)h(A)t(N)t(D)f FG(D)t(.)g(E)t(.)f(K)t FJ(E)t(Y)t(E)t(S)r FG(,)d Ft(Domain)f(decomposition)e(with)j(local)f (mesh)h(r)m(e\002nement)p FG(,)f(SIAM)512 2441 y(J.)21 b(Sci.)f(Statist.)h(Comput.,)e(13)h(\(1992\),)e(pp.)h(967\226993.)291 2613 y([111])41 b(I)t(.)24 b(G)t FJ(U)t(S)t(T)n(A)t(F)t(S)t(S)t(O)t(N)r FG(,)d Ft(A)f(class)h(of)f(\002r)o(st-or)m(der)h(factorization)e (methods)p FG(,)g(BIT)-6 b(,)20 b(18)g(\(1978\),)e(pp.)h(142\226156.) 291 2785 y([112])41 b(M)t(.)29 b(H)t(.)g(G)t FJ(U)t(T)t(K)t(N)t(E)t(C)t (H)t(T)r FG(,)c Ft(A)g(completed)e(theory)h(of)h(the)f(unsymmetric)h (Lanczos)f(pr)l(ocess)h(and)e(r)m(elated)512 2884 y(algorithms,)17 b(part)g(II)p FG(,)g(T)-6 b(ech.)17 b(Rep.)h(90-16,)d(IPS)j(Research)g (Report,)f(ETH)g(Z)7 b(\250)-35 b(urich,)17 b(Switzerland,)g(1990.)291 3056 y([113])p 512 3043 191 4 v 230 w(,)g Ft(The)g(unsymmetric)f (Lanczos)g(algorithms)f(and)h(their)g(r)m(elations)g(to)h(P)2753 3057 y(\264)2746 3056 y(ade)e(appr)l(oximation,)g(con-)512 3155 y(tinued)20 b(fr)o(actions)g(and)g(the)g(QD)h(algorithm)p FG(,)f(in)h(Proceedings)e(of)h(the)h(Copper)f(Mountain)f(Conference)512 3255 y(on)h(Iterati)n(v)o(e)f(Methods,)g(1990.)291 3427 y([114])p 512 3414 V 230 w(,)24 b Ft(V)-9 b(ariants)23 b(of)h(Bi-CGST)l(AB)f(for)h(matrices)g(with)g(comple)n(x)f(spectrum)p FG(,)h(T)-6 b(ech.)23 b(Rep.)g(91-14,)f(IPS)512 3526 y(ETH,)e(Z)7 b(\250)-35 b(urich,)19 b(Switzerland,)g(1991.)291 3698 y([115])p 512 3685 V 230 w(,)h Ft(A)f(completed)f(theory)h(of)g (the)h(unsymmetric)f(Lanczos)g(pr)l(ocess)g(and)g(r)m(elated)f (algorithms,)h(part)512 3797 y(I)p FG(,)h(SIAM)g(J.)h(Matrix)f(Anal.)g (Appl.,)f(13)h(\(1992\),)e(pp.)h(594\226639.)291 3969 y([116])41 b(W)l(.)h(H)t FJ(A)q(C)t(K)t(B)s(U)t(S)t(C)t(H)r FG(,)i Ft(Multi-Grid)37 b(Methods)g(and)f(Applications)p FG(,)j(Springer)n(-V)-9 b(erlag,)39 b(Berlin,)i(Ne)n(w)512 4069 y(Y)-9 b(ork,)19 b(1985.)291 4240 y([117])p 512 4227 V 230 w(,)38 b Ft(Iter)o(ative)c(L)1130 4241 y(\250)1123 4240 y(osung)f(gr)l(o\337er)h(sc)o(hwac)o(hbesetzter)f(Gleic)o (hungssysteme)p FG(,)j(T)-6 b(eubner)m(,)36 b(Stuttgart,)512 4340 y(1991.)291 4511 y([118])41 b(A)t(.)25 b(H)t FJ(A)t(D)t(J)t(I)t(D) t(I)t(M)t(O)t(S)r FG(,)e Ft(On)e(some)g(high)f(accur)o(acy)f(dif)o(fer) m(ence)h(sc)o(hemes)h(for)g(solving)g(elliptic)g(equations)p FG(,)512 4611 y(Numer)-5 b(.)19 b(Math.,)h(13)g(\(1969\),)e(pp.)h (396\226403.)291 4783 y([119])41 b(L)t(.)33 b(H)t FJ(A)q(G)t(E)t(M)t(A) t(N)i(A)t(N)t(D)f FG(D)t(.)f(Y)r FJ(O)t(U)t(N)t(G)r FG(,)f Ft(Applied)c(Iter)o(ative)h(Methods)p FG(,)h(Academic)f(Press,)j(Ne)n (w)d(Y)-9 b(ork,)512 4882 y(1981.)291 5054 y([120])41 b(W)l(.)25 b(H)t FJ(A)q(G)t(E)t(R)r FG(,)d Ft(Condition)d(estimator)o (s)p FG(,)h(SIAM)g(J.)h(Sci.)g(Statist.)g(Comput.,)e(5)h(\(1984\),)e (pp.)h(311\226316.)291 5225 y([121])41 b(M)t(.)21 b(H)t FJ(E)t(S)t(T)t(E)t(N)t(E)t(S)f(A)t(N)t(D)i FG(E)t(.)f(S)t FJ(T)t(I)t(E)t(F)t(E)t(L)r FG(,)c Ft(Methods)f(of)h(conjugate)e(gr)o (adients)h(for)h(solving)f(linear)h(systems)p FG(,)512 5325 y(J.)k(Res.)g(Nat.)f(Bur)-5 b(.)21 b(Stand.,)e(49)h(\(1952\),)e (pp.)h(409\226436.)291 5497 y([122])41 b(M)t(.)47 b(R)t(.)h(H)t FJ(E)t(S)t(T)t(E)t(N)t(E)t(S)r FG(,)g Ft(Conjugacy)41 b(and)h(gr)o(adients)p FG(,)47 b(in)c(A)g(History)f(of)h(Scienti\002c)g (Computing,)512 5596 y(Addison-W)-7 b(esle)o(y)i(,)18 b(Reading,)h(MA,)i(1990,)d(pp.)i(167\226179.)p eop end %%Page: 100 110 TeXDict begin 100 109 bop 739 282 a FG(100)2519 b Fu(BIBLIOGRAPHY)739 515 y FG([123])41 b(N)t(.)29 b(H)t FJ(I)t(G)t(H)t(A)t(M)r FG(,)e Ft(Experience)c(with)j(a)e(matrix)h(norm)f(estimator)p FG(,)i(SIAM)f(J.)g(Sci.)g(Statist.)g(Comput.,)g(11)960 615 y(\(1990\),)18 b(pp.)i(804\226809.)739 788 y([124])41 b(K)t(.)29 b(J)t FJ(E)t(A)g(A)t(N)t(D)g FG(D)t(.)g(Y)r FJ(O)t(U)t(N)t(G)r FG(,)c Ft(Gener)o(alized)f(conjugate-gr)o(adient)c (acceler)o(ation)i(of)i(nonsym-)f(metriz-)960 887 y(able)d(iter)o (ative)g(methods)p FG(,)f(Linear)h(Algebra)f(Appl.,)g(34)h(\(1980\),)e (pp.)h(159\226194.)739 1060 y([125])41 b(O)t(.)32 b(J)t FJ(O)t(H)t(N)t(S)t(O)t(N)t FG(,)j(C)t(.)d(M)t FJ(I)t(C)t(C)t(H)t(E)t(L) t(L)t(I)t FG(,)i FJ(A)t(N)t(D)e FG(G)t(.)g(P)m FJ(AU)t(L)r FG(,)e Ft(P)-7 b(olynomial)26 b(pr)m(econditioning)e(for)k(conjugate) 960 1160 y(gr)o(adient)19 b(calculation)p FG(,)f(SIAM)j(J.)f(Numer)-5 b(.)20 b(Anal.,)f(20)h(\(1983\),)e(pp.)i(362\226376.)739 1332 y([126])41 b(M)t(.)31 b(J)t FJ(O)t(N)t(E)t(S)f(A)t(N)t(D)h FG(P)-5 b(.)30 b(P)t FJ(L)t(A)t(S)t(S)t(M)t(A)t(N)t(N)r FG(,)f Ft(P)-7 b(ar)o(allel)25 b(solution)g(of)h(unstructed,)h(spar)o (se)f(systems)h(of)f(linear)960 1432 y(equations)p FG(,)e(in)h (Proceedings)f(of)g(the)h(Sixth)g(SIAM)g(conference)d(on)i(P)o(arallel) h(Processing)f(for)h(Scien-)960 1531 y(ti\002c)i(Computing,)e(R.)i (Sinco)o(v)o(ec,)f(D.)g(K)n(e)o(yes,)h(M.)f(Leuze,)g(L.)g(Petzold,)h (and)f(D.)g(Reed,)h(eds.,)g(SIAM,)960 1631 y(Philadelphia,)19 b(pp.)g(471\226475.)739 1804 y([127])p 960 1791 191 4 v 230 w(,)43 b Ft(A)38 b(par)o(allel)g(gr)o(aph)f(coloring)g(heuristic) p FG(,)42 b(SIAM)c(J.)h(Sci.)g(Statist.)g(Comput.,)i(14)d(\(1993\),)960 1903 y(pp.)20 b(654\226669.)739 2076 y([128])41 b(W)l(.)21 b(J)t FJ(O)t(U)t(B)t(E)t(RT)r FG(,)c Ft(Lanczos)f(methods)e(for)i(the)g (solution)e(of)i(nonsymmetric)e(systems)j(of)f(linear)f(equations)p FG(,)960 2176 y(SIAM)21 b(J.)f(Matrix)g(Anal.)g(Appl.,)f(13)h (\(1992\),)e(pp.)h(926\226943.)739 2348 y([129])41 b(W)l(.)25 b(K)t FJ(A)t(H)t(A)t(N)r FG(,)20 b Ft(Gauss-Seidel)e(methods)h(of)h (solving)e(lar)m(g)o(e)i(systems)g(of)g(linear)f(equations)p FG(,)f(PhD)i(thesis,)960 2448 y(Uni)n(v)o(ersity)f(of)h(T)-7 b(oronto,)18 b(1958.)739 2621 y([130])41 b(S)t(.)31 b(K)t FJ(A)t(N)t(I)t(E)t(L)r FG(,)d Ft(Estimates)e(for)h(some)f (computational)d(tec)o(hniques)i(in)h(linear)g(alg)o(ebr)o(a)p FG(,)g(Mathematics)960 2720 y(of)20 b(Computation,)e(20)i(\(1966\),)e (pp.)h(369\226378.)739 2893 y([131])41 b(D)t(.)30 b(K)t FJ(E)t(R)t(S)t(H)t(A)n(W)r FG(,)c Ft(The)g(incomplete)d(Cholesk)o (y-conjugate)g(gr)o(adient)g(method)h(for)i(the)f(iter)o(ative)g(solu-) 960 2993 y(tion)20 b(of)h(systems)g(of)f(linear)g(equations)p FG(,)f(J.)i(Comput.)e(Phys.,)g(26)h(\(1978\),)e(pp.)h(43\22665.)739 3165 y([132])41 b(R)t(.)28 b(K)t FJ(E)t(T)t(T)t(L)t(E)t(R)r FG(,)23 b Ft(Analysis)g(and)f(comparison)g(of)h(r)m(elaxation)f(sc)o (hemes)h(in)g(r)l(ob)n(ust)h(multigrid)e(and)g(pr)m(e-)960 3265 y(conditioned)15 b(conjugate)f(gr)o(adient)i(methods)p FG(,)g(in)h(Multigrid)e(Methods,)i(Lecture)f(Notes)h(in)f(Mathemat-)960 3365 y(ics)24 b(960,)e(W)-8 b(.)24 b(Hackb)n(usch)d(and)h(U.)h(T)m (rottenber)o(g,)d(eds.,)j(Springer)n(-V)-9 b(erlag,)21 b(Berlin,)i(Ne)n(w)g(Y)-9 b(ork,)22 b(1982,)960 3464 y(pp.)e(502\226534.)739 3637 y([133])p 960 3624 V 230 w(,)25 b Ft(Linear)f(multigrid)f(methods)g(in)g(numerical)g(r)m (eservoir)i(simulation)p FG(,)e(PhD)h(thesis,)h(Delft)e(Uni-)960 3737 y(v)o(ersity)d(of)g(T)-6 b(echnology)h(,)17 b(Delft,)j(The)g (Netherlands,)e(1987.)739 3909 y([134])41 b(D)t(.)36 b(E)t(.)g(K)t FJ(E)t(Y)t(E)t(S)t FG(,)j(T)n(.)c(F)m(.)i(C)t FJ(H)t(A)t(N)t FG(,)j(G)t(.)c(M)t FJ(E)t(U)t(R)t(A)t(N)t(T)o FG(,)i(J)t(.)f(S)t(.)f(S)t FJ(C)t(R)q(O)t(G)t(G)t(S)t FG(,)41 b FJ(A)t(N)t(D)36 b FG(R)t(.)g(G)t(.)h(V)q FJ(O)t(I)t(G)t(T)r FG(,)d(eds.,)960 4009 y Ft(Domain)28 b(Decomposition)f(Methods)h(F)-9 b(or)29 b(P)-7 b(artial)29 b(Dif)o(fer)m(ential)f(Equations)p FG(,)h(SIAM,)g(Philadelphia,)960 4108 y(1992.)k(Proceedings)20 b(of)h(the)h(Fifth)g(International)d(Symposium)h(on)h(Domain)g (Decomposition)f(Meth-)960 4208 y(ods,)g(Norfolk,)e(V)-11 b(A,)21 b(1991.)739 4381 y([135])41 b(D)t(.)29 b(E)t(.)g(K)t FJ(E)t(Y)t(E)t(S)f(A)t(N)t(D)h FG(W)l(.)h(D)t(.)f(G)t FJ(R)q(O)t(P)t(P)r FG(,)e Ft(A)d(comparison)f(of)i(domain)e (decomposition)f(tec)o(hniques)h(for)960 4480 y(elliptic)18 b(partial)f(dif)o(fer)m(ential)g(equations)f(and)h(their)h(par)o(allel) f(implementation)p FG(,)f(SIAM)i(J.)g(Sci.)g(Statist.)960 4580 y(Comput.,)h(8)h(\(1987\),)e(pp.)i(s166)f(\226)i(s202.)739 4753 y([136])p 960 4740 V 230 w(,)f Ft(Domain)e(decomposition)g(for)h (nonsymmetric)g(systems)i(of)e(equations:)k(Examples)c(fr)l(om)h(com-) 960 4852 y(putational)32 b(\003uid)g(dynamics)p FG(,)k(in)e(Domain)f (Decomposition)e(Methods,)36 b(proceedings)31 b(of)j(the)f(Sec-)960 4952 y(ond)e(Internation)e(Symposium,)j(Los)g(Angeles,)h(California,)g (January)e(14\22616,)h(1988,)g(T)-6 b(.)31 b(F)-7 b(.)33 b(Chan,)960 5052 y(R.)21 b(Glo)n(winski,)f(J.)g(Periaux,)f(and)h(O.)h (B.)f(W)m(idlund,)f(eds.,)h(Philadelphia,)f(1989,)f(SIAM,)i(pp.)g (373\226384.)739 5224 y([137])p 960 5211 V 230 w(,)h Ft(Domain)f(decomposition)f(tec)o(hniques)g(for)i(the)f(par)o(allel)g (solution)g(of)h(nonsymmetric)f(systems)960 5324 y(of)h(elliptic)f (boundary)e(value)i(pr)l(oblems)p FG(,)f(Applied)h(Num.)f(Math.,)h(6)g (\(1989/1990\),)c(pp.)j(281\226301.)739 5497 y([138])41 b(S)t(.)30 b(K)t(.)f(K)t FJ(I)t(M)h(A)t(N)t(D)f FG(A)t(.)g(T)n(.)g(C)t FJ(H)t(R)q(O)t(N)t(O)t(P)t(O)t(U)t(L)t(O)t(S)r FG(,)e Ft(A)e(class)h(of)e(Lanczos-lik)o(e)g(algorithms)g(implemented)960 5596 y(on)c(par)o(allel)f(computer)o(s)p FG(,)h(P)o(arallel)g(Comput.,) f(17)h(\(1991\),)e(pp.)h(763\226778.)p eop end %%Page: 101 111 TeXDict begin 101 110 bop 291 282 a Fu(BIBLIOGRAPHY)2520 b FG(101)291 515 y([139])41 b(D)t(.)34 b(R)t(.)h(K)t FJ(I)t(N)t(C)t(A)t(I)t(D)t FG(,)i(J)t(.)e(R)t(.)f(R)t FJ(E)t(S)t(P)t(E)t(S)t(S)t FG(,)j(D)t(.)d(M)t(.)g(Y)r FJ(O)t(U)t(N)t(G)t FG(,)j FJ(A)t(N)t(D)d FG(R)t(.)h(G)t(.)f(G)t FJ(R)t(I)t(M)t(E)t(S)r FG(,)f Ft(ITP)-7 b(A)n(CK)29 b(2C:)h(A)512 615 y(Fortr)o(an)c(pac)n(ka)o(g)o(e)g(for)i(solving)e(lar)m(g)o(e)h (spar)o(se)h(linear)f(systems)h(by)g(adaptive)d(acceler)o(ated)h(iter)o (ative)512 715 y(methods)p FG(,)19 b(A)m(CM)i(T)m(rans.)e(Math.)h (Soft.,)g(8)g(\(1982\),)e(pp.)h(302\226322.)27 b(Algorithm)18 b(586.)291 879 y([140])41 b(L)t(.)25 b(Y)-7 b(.)26 b(K)r FJ(O)t(L)t(O)q(T)t(I)t(L)t(I)t(N)r(A)f(A)t(N)t(D)h FG(A)t(.)f(Y)-7 b(.)26 b(Y)t FJ(E)t(R)t(E)t(M)t(I)t(N)r FG(,)21 b Ft(On)g(a)g(family)g (of)g(two-le)o(vel)g(pr)m(econditionings)d(of)j(the)512 978 y(incomlete)f(bloc)n(k)h(factorization)e(type)p FG(,)i(So)o(v)-5 b(.)20 b(J.)h(Numer)-5 b(.)20 b(Anal.)h(Math.)f(Modelling,)f(\(1986\),) g(pp.)h(293\226)512 1078 y(320.)291 1242 y([141])41 b(C)t(.)28 b(L)t FJ(A)t(N)t(C)t(Z)t(O)t(S)r FG(,)c Ft(An)f(iter)o(ation)f(method)g (for)i(the)f(solution)f(of)h(the)g(eig)o(en)m(value)e(pr)l(oblem)i(of)g (linear)g(dif-)512 1342 y(fer)m(ential)d(and)f(inte)m(gr)o(al)g(oper)o (ator)o(s)p FG(,)h(J.)g(Res.)i(Nat.)e(Bur)-5 b(.)20 b(Stand.,)g(45)g (\(1950\),)d(pp.)j(255\226282.)291 1506 y([142])p 512 1493 191 4 v 230 w(,)34 b Ft(Solution)29 b(of)h(systems)i(of)f(linear)g (equations)e(by)i(minimized)f(iter)o(ations)p FG(,)j(J.)e(Res.)h(Nat.)f (Bur)-5 b(.)512 1605 y(Stand.,)19 b(49)h(\(1952\),)e(pp.)h(33\22653.) 291 1769 y([143])41 b(C)t(.)30 b(L)t FJ(A)n(W)t(S)t(O)t(N)t FG(,)h(R)t(.)f(H)t FJ(A)t(N)t(S)t(O)t(N)t FG(,)i(D)t(.)d(K)t FJ(I)t(N)t(C)t(A)t(I)t(D)t FG(,)k FJ(A)t(N)t(D)d FG(F)m(.)g(K)t FJ(R)q(O)t(G)t(H)r FG(,)e Ft(Basic)d(Linear)g(Alg)o(ebr)o(a)g(Subpr)l (o-)512 1869 y(gr)o(ams)20 b(for)h(FORTRAN)f(usa)o(g)o(e)p FG(,)f(A)m(CM)i(T)m(rans.)e(Math.)h(Soft.,)g(5)g(\(1979\),)e(pp.)i (308\226325.)291 2033 y([144])41 b(J)t(.)21 b(M)t FJ(A)t(I)t(T)t(R)t(E) g(A)t(N)t(D)g FG(F)m(.)h(M)t FJ(U)t(S)t(Y)r FG(,)c Ft(The)e(contr)o (action)f(number)g(of)i(a)f(class)h(of)g(two-le)o(vel)f(methods;)h(an)f (e)n(xact)512 2133 y(e)o(valuation)27 b(for)i(some)g(\002nite)f (element)h(subspaces)f(and)g(model)g(pr)l(oblems)p FG(,)j(in)e (Multigrid)e(methods,)512 2232 y(Proceedings,)20 b(K)7 b(\250)-35 b(oln-Porz,)20 b(1981,)h(W)-8 b(.)23 b(Hackb)n(usch)d(and)h (U.)h(T)m(rottenber)o(g,)d(eds.,)j(v)n(ol.)g(960)e(of)i(Lecture)512 2332 y(Notes)e(in)h(Mathematics,)e(1982,)g(pp.)g(535\226544.)291 2496 y([145])41 b(T)n(.)19 b(M)t FJ(A)t(N)t(T)t(E)t(U)t(FF)t(E)t(L)r FG(,)d Ft(The)f(Tc)o(hebyc)o(he)o(v)e(iter)o(ation)h(for)i (nonsymmetric)f(linear)g(systems)p FG(,)i(Numer)-5 b(.)15 b(Math.,)512 2596 y(28)20 b(\(1977\),)e(pp.)h(307\226327.)291 2760 y([146])p 512 2747 V 230 w(,)g Ft(An)f(incomplete)f(factorization) h(tec)o(hnique)e(for)j(positive)g(de\002nite)e(linear)h(systems)p FG(,)i(Mathemat-)512 2859 y(ics)h(of)f(Computation,)e(34)i(\(1980\),)e (pp.)h(473\226497.)291 3024 y([147])41 b(S)t(.)32 b(M)t FJ(C)t FG(C)t FJ(O)t(R)t(M)t(I)t(C)t(K)r FG(,)h Ft(Multile)o(vel)27 b(Adaptive)g(Methods)g(for)h(P)-7 b(artial)28 b(Dif)o(fer)m(ential)f (Equations)p FG(,)h(SIAM,)512 3123 y(Philadelphia,)19 b(1989.)291 3287 y([148])41 b(S)t(.)32 b(M)t FJ(C)t FG(C)t FJ(O)t(R)t(M)t(I)t(C)t(K)i(A)t(N)t(D)e FG(J)t(.)g(T)t FJ(H)t(O)t(M)t(A)t(S)r FG(,)d Ft(The)e(Fast)h(Adaptive)e(Composite)g (grid)i(\(F)-10 b(A)n(C\))26 b(method)g(for)512 3387 y(elliptic)20 b(equations)p FG(,)f(Mathematics)g(of)h(Computation,)e (46)i(\(1986\),)e(pp.)i(439\226456.)291 3551 y([149])41 b(U)t(.)21 b(M)t FJ(E)t(I)t(E)t(R)h(A)t(N)t(D)f FG(A)t(.)h(S)t FJ(A)t(M)t(E)t(H)r FG(,)c Ft(The)f(behavior)f(of)h(conjugate)e(gr)o (adient)g(algorithms)i(on)f(a)h(multivector)512 3651 y(pr)l(ocessor)j(with)h(a)f(hier)o(ar)m(c)o(hical)f(memory)p FG(,)h(J.)h(Comput.)e(Appl.)g(Math.,)h(24)g(\(1988\),)e(pp.)h (13\22632.)291 3815 y([150])41 b(U)t(.)22 b(M)t FJ(E)t(I)t(E)t(R)t FG(-)t(Y)-5 b FJ(A)t(N)t(G)r FG(,)19 b Ft(Pr)m(econditioned)c (conjugate)g(gr)o(adient-lik)o(e)h(methods)h(for)h(nonsymmetric)f (linear)512 3914 y(systems)p FG(,)k(tech.)f(rep.,)f(CSRD,)j(Uni)n(v)o (ersity)c(of)i(Illinois,)g(Urbana,)f(IL,)h(April)g(1992.)291 4078 y([151])41 b(J)t(.)31 b(M)t FJ(E)t(I)t(J)t(E)t(R)t(I)t(N)t(K)f(A)t (N)t(D)h FG(H)t(.)f FJ(V)-5 b(A)t(N)31 b(D)t(E)t(R)f FG(V)q FJ(O)t(R)t(S)t(T)r FG(,)e Ft(An)d(iter)o(ative)h(solution)f (method)g(for)h(linear)g(systems)512 4178 y(of)e(whic)o(h)f(the)h(coef) o(\002cient)e(matrix)i(is)h(a)f(symmetric)g FC(M)9 b Ft(-matrix)p FG(,)24 b(Mathematics)f(of)h(Computation,)e(31)512 4278 y(\(1977\),)c(pp.)h(148\226162.)291 4442 y([152])p 512 4429 V 230 w(,)g Ft(Guidelines)g(for)g(the)g(usa)o(g)o(e)f(of)h (incomplete)f(decompositions)f(in)i(solving)f(sets)i(of)g(linear)e (equa-)512 4541 y(tions)i(as)h(the)n(y)e(occur)h(in)g(pr)o(actical)g (pr)l(oblems)p FG(,)g(J.)g(Comput.)f(Phys.,)h(44)g(\(1981\),)d(pp.)j (134\226155.)291 4705 y([153])41 b(R)t(.)29 b(M)t FJ(E)t(L)t(H)t(E)t(M) r FG(,)c Ft(T)-8 b(owar)m(d)24 b(ef)o(\002cient)f(implementation)f(of)i (pr)m(econditioned)d(conjugate)i(gr)o(adient)f(meth-)512 4805 y(ods)e(on)g(vector)g(super)m(computer)o(s)p FG(,)f(Internat.)g (J.)h(Supercomput.)e(Appls.,)h(1)i(\(1987\),)c(pp.)j(77\22698.)291 4969 y([154])41 b(G)t(.)29 b(M)t FJ(E)t(U)t(R)t(A)t(N)t(T)r FG(,)c Ft(The)g(bloc)n(k)f(pr)m(econditioned)d(conjugate)h(gr)o(adient) h(method)g(on)h(vector)h(computer)o(s)p FG(,)512 5069 y(BIT)-6 b(,)20 b(24)g(\(1984\),)e(pp.)h(623\226633.)291 5233 y([155])p 512 5220 V 230 w(,)e Ft(Multitasking)f(the)g(conjugate)f (gr)o(adient)f(method)i(on)g(the)g(CRA)-5 b(Y)17 b(X-MP/48)p FG(,)f(P)o(arallel)g(Comput.,)512 5333 y(5)k(\(1987\),)e(pp.)i (267\226280.)291 5497 y([156])41 b(N)t(.)34 b(M)t FJ(U)t(N)t(K)t(S)t(G) t(A)t(A)t(R)t(D)r FG(,)f Ft(Solving)c(spar)o(se)h(symmetric)h(sets)f (of)g(linear)g(equations)e(by)i(pr)m(econditioned)512 5596 y(conjugate)18 b(gr)o(adients)p FG(,)h(A)m(CM)i(T)m(rans.)e(Math.) h(Softw)o(are,)f(6)i(\(1980\),)c(pp.)j(206\226219.)p eop end %%Page: 102 112 TeXDict begin 102 111 bop 739 282 a FG(102)2519 b Fu(BIBLIOGRAPHY)739 515 y FG([157])41 b(N)t(.)26 b(N)q FJ(A)q(C)t(H)t(T)t(I)t(G)t(A)t(L)t FG(,)g(S)t(.)g(R)t FJ(E)t(D)t(DY)-6 b FG(,)26 b FJ(A)t(N)t(D)g FG(L)t(.)f(T)t FJ(R)t(E)t(F)t(E)t(T)t(H)t(E)t(N)r FG(,)20 b Ft(How)i(fast)f(ar)m(e)g(nonsymmetric)f(matrix)h(iter)n(-)960 615 y(ations?)p FG(,)e(SIAM)i(J.)f(Matrix)g(Anal.)g(Appl.,)f(13)h (\(1992\),)e(pp.)h(778\226795.)739 791 y([158])41 b(N)t(.)27 b(N)q FJ(A)q(C)t(H)t(T)t(I)t(G)t(A)t(L)t FG(,)h(L)t(.)e(R)t FJ(E)t(I)t(C)t(H)t(E)t(L)t FG(,)h FJ(A)t(N)t(D)g FG(L)t(.)f(T)t FJ(R)t(E)t(F)t(E)t(T)t(H)t(E)t(N)r FG(,)c Ft(A)g(hybrid)f(GMRES)h (algorithm)f(for)h(non-)960 890 y(symmetric)f(matrix)g(iter)o(ations)p FG(,)e(T)-6 b(ech.)20 b(Rep.)g(90-7,)f(MIT)-6 b(,)19 b(Cambridge,)g(MA,)h(1990.)739 1066 y([159])41 b(N)t(.)25 b(M)t(.)f(N)q FJ(A)q(C)t(H)t(T)t(I)t(G)t(A)t(L)r FG(,)d Ft(A)g(Look-Ahead)c(V)-9 b(ariant)19 b(of)h(the)g(Lanczos)g(Algorithm)f (and)g(its)i(Application)d(to)960 1166 y(the)k(Quasi-Minimal)e (Residual)h(Methods)g(for)h(Non-Hermitian)f(Linear)g(Systems)p FG(,)i(PhD)e(thesis,)i(MIT)-6 b(,)960 1265 y(Cambridge,)19 b(MA,)h(1991.)739 1441 y([160])41 b(Y)-7 b(.)28 b(N)t FJ(O)q(T)n(A)m(Y)r FG(,)d Ft(Solving)d(positive)h(\(semi\)de\002nite)f (linear)h(systems)i(by)e(pr)m(econditioned)d(iter)o(ative)k(meth-)960 1541 y(ods)p FG(,)29 b(in)e(Preconditioned)d(Conjugate)i(Gradient)g (Methods,)h(O.)h(Ax)o(elsson)e(and)g(L.)i(K)m(olotilina,)f(eds.,)960 1640 y(v)n(ol.)20 b(1457)f(of)h(Lecture)f(Notes)i(in)f(Mathematics,)f (Nijme)o(gen,)g(1989,)g(pp.)g(105\226125.)739 1816 y([161])p 960 1803 191 4 v 230 w(,)h Ft(On)f(the)h(r)l(ob)n(ustness)g(of)f (modi\002ed)f(incomplete)g(factorization)h(methods)p FG(,)f(Internat.)g(J.)i(Comput.)960 1916 y(Math.,)g(40)g(\(1992\),)d (pp.)j(121\226141.)739 2092 y([162])41 b(D)t(.)23 b(O)t(')t(L)t FJ(E)t(A)t(RY)r FG(,)c Ft(The)g(bloc)n(k)g(conjugate)d(gr)o(adient)i (algorithm)f(and)h(r)m(elated)g(methods)p FG(,)g(Linear)g(Algebra)960 2191 y(Appl.,)i(29)f(\(1980\),)f(pp.)i(293\226322.)739 2367 y([163])p 960 2354 V 230 w(,)31 b Ft(Or)m(dering)d(sc)o(hemes)g (for)g(par)o(allel)g(pr)l(ocessing)g(of)g(certain)g(mesh)h(pr)l(oblems) p FG(,)h(SIAM)e(J.)h(Sci.)960 2467 y(Statist.)21 b(Comput.,)e(5)h (\(1984\),)e(pp.)i(620\226632.)739 2643 y([164])41 b(T)n(.)28 b(C)t(.)g(O)t FJ(P)t(P)t(E)t FG(,)h(W)l(.)g(D)t(.)f(J)t FJ(O)t(U)t(B)t(E)t(RT)o FG(,)h FJ(A)t(N)t(D)f FG(D)t(.)g(R)t(.)h(K)t FJ(I)t(N)t(C)t(A)t(I)t(D)r FG(,)d Ft(NSPCG)e(user')m(s)f(guide)o(,)g (ver)o(sion)h(1.0:)31 b(A)960 2742 y(pac)n(ka)o(g)o(e)d(for)h(solving)g (lar)m(g)o(e)g(spar)o(se)g(linear)g(systems)h(by)f(various)g(iter)o (ative)g(methods)p FG(,)h(T)-6 b(ech.)28 b(Rep.)960 2842 y(CN)m(A\226216,)19 b(Center)g(for)g(Numerical)g(Analysis,)h(Uni)n(v)o (ersity)e(of)i(T)-6 b(e)o(xas)19 b(at)i(Austin,)e(Austin,)h(TX,)f (April)960 2941 y(1988.)739 3117 y([165])41 b(J)t(.)36 b(M)t(.)f(O)t FJ(RT)t(E)t(G)t(A)r FG(,)e Ft(Intr)l(oduction)28 b(to)j(P)-7 b(ar)o(allel)30 b(and)g(V)-9 b(ector)30 b(Solution)f(of)h (Linear)h(Systems)p FG(,)i(Plenum)960 3217 y(Press,)21 b(Ne)n(w)f(Y)-9 b(ork)20 b(and)f(London,)f(1988.)739 3393 y([166])41 b(C)t(.)27 b(P)m FJ(A)t(I)t(G)t(E)t FG(,)g(B)t(.)f(P)m FJ(A)t(R)t(L)t(E)t(T)t(T)o FG(,)f FJ(A)t(N)t(D)i FG(H)t(.)f(V)-6 b FJ(A)t(N)26 b(D)t(E)t(R)g FG(V)q FJ(O)t(R)t(S)t(T)r FG(,)c Ft(Appr)l(oximate)f(solutions)g(and)f(eig)o(en)m(value)960 3492 y(bounds)f(fr)l(om)i(Krylo)o(v)g(subspaces)p FG(,)e(Numer)-5 b(.)19 b(Lin.)h(Alg.)g(Appls.,)g(to)g(appear)-5 b(.)739 3668 y([167])41 b(C)t(.)33 b(P)m FJ(A)t(I)t(G)t(E)g(A)t(N)t(D)g FG(M)t(.)f(S)t FJ(AU)t(N)t(D)t(E)t(R)t(S)r FG(,)f Ft(Solution)26 b(of)i(spar)o(se)h(inde\002nite)d(systems)j(of)f(linear)g(equations)p FG(,)960 3768 y(SIAM)21 b(J.)f(Numer)-5 b(.)20 b(Anal.,)g(12)f (\(1975\),)f(pp.)i(617\226629.)739 3944 y([168])41 b(C)t(.)26 b(C)t(.)f(P)m FJ(A)t(I)t(G)t(E)g(A)t(N)t(D)g FG(M)t(.)g(A)t(.)g(S)t FJ(AU)t(N)t(D)t(E)t(R)t(S)r FG(,)c Ft(LSQR:)f(An)g(algorithm)g(for)g (spar)o(se)h(linear)f(equations)f(and)960 4043 y(spar)o(se)i(least)g (squar)m(es)p FG(,)e(A)m(CM)i(T)m(rans.)e(Math.)h(Soft.,)g(8)g (\(1982\),)e(pp.)i(43\22671.)739 4219 y([169])41 b(G)t(.)27 b(P)m FJ(AO)t(L)t(I)t(N)t(I)h(A)t(N)t(D)f FG(G)t(.)g(R)t FJ(A)t(D)t(I)t(C)t(A)m(T)t(I)h(D)t(I)f FG(B)t FJ(R)q(O)t(Z)t(O)t(L)t(O) r FG(,)d Ft(Data)e(structur)m(es)h(to)g(vectorize)g(CG)g(algorithms)960 4319 y(for)e(g)o(ener)o(al)e(spar)o(sity)i(patterns)p FG(,)f(BIT)-6 b(,)20 b(29)g(\(1989\),)d(pp.)j(703\226718.)739 4494 y([170])41 b(B)t(.)25 b(P)m FJ(A)t(R)t(L)t(E)t(T)t(T)r FG(,)c Ft(The)f(symmetric)h(eig)o(en)m(value)d(pr)l(oblem)p FG(,)i(Prentice-Hall,)f(London,)f(1980.)739 4670 y([171])41 b(B)t(.)35 b(N)t(.)g(P)m FJ(A)t(R)t(L)t(E)t(T)t(T)o FG(,)h(D)t(.)f(R)t (.)g(T)m FJ(A)m(Y)t(L)t(O)t(R)t FG(,)j FJ(A)t(N)t(D)d FG(Z)t(.)f(A)t(.)h(L)t FJ(I)t(U)r FG(,)e Ft(A)d(look-ahead)e(Lanczos)i (algorithm)f(for)960 4770 y(unsymmetric)20 b(matrices)p FG(,)h(Mathematics)e(of)h(Computation,)e(44)i(\(1985\),)e(pp.)h (105\226124.)739 4946 y([172])41 b(D)t(.)26 b(P)t FJ(E)t(A)q(C)t(E)t(M) t(A)t(N)h(A)t(N)t(D)f(J)t FG(.)g(H)t(.)t(H)t(.)g(R)t FJ(A)q(C)t(H)t(F)t(O)t(R)t(D)r FG(,)e Ft(The)e(numerical)f(solution)f (of)i(par)o(abolic)d(and)i(elliptic)960 5045 y(dif)o(fer)m(ential)e (equations)p FG(,)g(J.)i(Soc.)f(Indust.)f(Appl.)g(Math.,)h(3)g (\(1955\),)e(pp.)h(28\22641.)739 5221 y([173])41 b(C)t(.)31 b(P)t FJ(O)t(M)t(M)t(E)t(R)t(E)t(L)t(L)r FG(,)c Ft(Solution)d(of)i(Lar) m(g)o(e)g(Unsymmetric)g(Systems)g(of)g(Linear)g(Equations)p FG(,)f(v)n(ol.)g(17)h(of)960 5321 y(Series)21 b(in)f (Micro-electronics,)e(v)n(olume)h(17,)h(Hartung-Gorre)d(V)-9 b(erlag,)19 b(K)m(onstanz,)g(1992.)739 5497 y([174])p 960 5484 V 230 w(,)h Ft(Solution)d(of)h(lar)m(g)o(e)h(unsymmetric)g (systems)h(of)e(linear)h(equations)p FG(,)e(PhD)i(thesis,)h(Swiss)g (Federal)960 5596 y(Institute)g(of)g(T)-6 b(echnology)h(,)17 b(Z)7 b(\250)-35 b(urich,)19 b(Switzerland,)g(1992.)p eop end %%Page: 103 113 TeXDict begin 103 112 bop 291 282 a Fu(BIBLIOGRAPHY)2520 b FG(103)291 515 y([175])41 b(E)t(.)32 b(P)t FJ(O)t(O)t(L)t(E)g(A)t(N)t (D)g FG(J)t(.)h(O)t FJ(RT)t(E)t(G)t(A)r FG(,)c Ft(Multicolor)f(ICCG)g (methods)f(for)h(vector)g(computer)o(s)p FG(,)h(T)-6 b(ech.)27 b(Rep.)512 615 y(RM)33 b(86-06,)g(Department)d(of)i(Applied)f (Mathematics,)j(Uni)n(v)o(ersity)d(of)h(V)-5 b(ir)o(ginia,)34 b(Charlottesville,)512 715 y(V)-11 b(A,)20 b(1986.)291 885 y([176])41 b(A)t(.)28 b(Q)s FJ(U)q(A)t(RT)t(E)t(R)q(O)t(N)t(I)r FG(,)f(ed.,)d Ft(Domain)e(Decomposition)g(Methods,)i(Pr)l(oceedings)f (of)g(the)h(Sixth)f(Interna-)512 984 y(tional)d(Symposium)g(on)h (Domain)f(Decomposition)f(Methods,)i(Como,)g(Italy)-5 b(,)p FG(,)21 b(Pro)o(vidence,)e(RI,)j(1993,)512 1084 y(AMS.)29 b(to)21 b(appear)-5 b(.)291 1254 y([177])41 b(G)t(.)29 b(R)t FJ(A)t(D)t(I)t(C)t(A)m(T)t(I)i(D)t(I)e FG(B)t FJ(R)q(O)t(Z)t(O)t(L)t(O)i(A)t(N)t(D)e FG(Y)-7 b(.)30 b(R)q FJ(O)t(B)t(E)t(RT)r FG(,)d Ft(V)-9 b(ector)25 b(and)f(par)o(allel)g(CG-lik)o(e)h(algorithms)f(for)512 1353 y(spar)o(se)d(non-symmetric)e(systems)p FG(,)i(T)-6 b(ech.)20 b(Rep.)g(681-M,)e(IMA)m(G/TIM3,)h(Grenoble,)f(France,)h (1987.)291 1523 y([178])41 b(J)t(.)30 b(R)t FJ(E)t(I)t(D)r FG(,)d Ft(On)f(the)f(method)f(of)i(conjugate)d(gr)o(adients)h(for)i (the)f(solution)g(of)g(lar)m(g)o(e)g(spar)o(se)h(systems)h(of)512 1623 y(linear)g(equations)p FG(,)f(in)h(Lar)o(ge)e(Sparse)i(Sets)h(of)e (Linear)g(Equations,)h(J.)g(Reid,)i(ed.,)e(Academic)f(Press,)512 1723 y(London,)18 b(1971,)g(pp.)i(231\226254.)291 1892 y([179])41 b(G)t(.)27 b(R)q FJ(O)t(D)t(R)t(I)t(G)t(U)t(E)h(A)t(N)t(D)f FG(D)t(.)f(W)s FJ(O)t(L)t(I)t(T)t(Z)t(E)t(R)r FG(,)d Ft(Pr)m(econditioning)d(by)i(incomplete)f(bloc)n(k)h(cyclic)g(r)m (eduction)p FG(,)512 1992 y(Mathematics)e(of)f(Computation,)g(42)g (\(1984\),)f(pp.)i(549\226565.)291 2162 y([180])41 b(Y)-7 b(.)23 b(S)t FJ(A)t(A)t(D)r FG(,)d Ft(The)e(Lanczos)g(biortho)o (gonalization)d(algorithm)i(and)h(other)g(oblique)f(pr)l(ojection)h (methods)512 2262 y(for)j(solving)e(lar)m(g)o(e)h(unsymmetric)g (systems)p FG(,)h(SIAM)g(J.)g(Numer)-5 b(.)19 b(Anal.,)h(19)f (\(1982\),)f(pp.)i(485\226506.)291 2432 y([181])p 512 2419 191 4 v 230 w(,)27 b Ft(Pr)o(actical)f(use)g(of)g(some)g(Krylo)o (v)g(subspace)f(methods)g(for)h(solving)g(inde\002nite)e(and)h(nonsym-) 512 2531 y(metric)c(linear)f(systems)p FG(,)h(SIAM)f(J.)h(Sci.)g (Statist.)g(Comput.,)e(5)h(\(1984\),)e(pp.)h(203\226228.)291 2701 y([182])p 512 2688 V 230 w(,)37 b Ft(Pr)o(actical)32 b(use)i(of)g(polynomial)d(pr)m(econditionings)g(for)i(the)h(conjugate)d (gr)o(adient)h(method)p FG(,)512 2801 y(SIAM)20 b(J.)h(Sci.)g(Statist.) g(Comput.,)e(6)h(\(1985\),)e(pp.)h(865\226881.)291 2971 y([183])p 512 2958 V 230 w(,)k Ft(Pr)m(econditioning)c(tec)o(hniques)i (for)h(inde\002nite)f(and)g(nonsymmetric)h(linear)g(systems)p FG(,)h(J.)g(Com-)512 3070 y(put.)d(Appl.)f(Math.,)h(24)f(\(1988\),)f (pp.)i(89\226105.)291 3240 y([184])p 512 3227 V 230 w(,)37 b Ft(Krylo)o(v)d(subspace)f(methods)g(on)g(super)m(computer)o(s)p FG(,)i(SIAM)f(J.)g(Sci.)g(Statist.)h(Comput.,)g(10)512 3340 y(\(1989\),)18 b(pp.)h(1200\2261232.)291 3510 y([185])p 512 3497 V 230 w(,)31 b Ft(SP)-7 b(ARSKIT:)27 b(A)h(basic)h(tool)f(kit) h(for)g(spar)o(se)g(matrix)g(computation)p FG(,)g(T)-6 b(ech.)28 b(Rep.)g(CSRD)i(TR)512 3610 y(1029,)18 b(CSRD,)k(Uni)n(v)o (ersity)d(of)h(Illinois,)f(Urbana,)g(IL,)h(1990.)291 3780 y([186])p 512 3767 V 230 w(,)k Ft(A)g(\003e)n(xible)f(inner)n (-outer)f(pr)m(econditioned)f(GMRES)i(algorithm)p FG(,)g(SIAM)g(J.)h (Sci.)g(Comput.,)e(14)512 3879 y(\(1993\),)c(pp.)h(461\226469.)291 4049 y([187])41 b(Y)-7 b(.)25 b(S)t FJ(A)t(A)t(D)h(A)t(N)t(D)f FG(M)t(.)g(S)t FJ(C)t(H)t(U)t(L)n(T)t(Z)r FG(,)c Ft(Conjugate)e(gr)o (adient-lik)o(e)g(algorithms)h(for)h(solving)f(nonsymmetric)512 4149 y(linear)g(systems)p FG(,)h(Mathematics)f(of)g(Computation,)e(44)i (\(1985\),)d(pp.)j(417\226424.)291 4319 y([188])p 512 4306 V 230 w(,)i Ft(GMRES:)g(A)g(g)o(ener)o(alized)e(minimal)i(r)m (esidual)f(algorithm)g(for)i(solving)e(nonsymmetric)g(linear)512 4418 y(systems)p FG(,)g(SIAM)f(J.)h(Sci.)g(Statist.)g(Comput.,)e(7)h (\(1986\),)e(pp.)h(856\226869.)291 4588 y([189])41 b(G)t(.)30 b(L)t(.)g(G)t(.)h(S)t FJ(L)t(E)t(I)t(J)t(P)t(E)t(N)f(A)t(N)t(D)g FG(D)t(.)h(R)t(.)g(F)t FJ(O)t(K)t(K)t(E)t(M)t(A)r FG(,)c Ft(Bi-CGST)l(AB\()p FC(`)p Ft(\))d(for)j(linear)e(equations)g(in)m (volving)512 4688 y(unsymmetric)h(matrices)g(with)h(comple)n(x)e (spectrum)p FG(,)j(T)-6 b(ech.)25 b(Rep.)h(772,)h(Uni)n(v)o(ersity)d (of)i(Utrecht,)h(De-)512 4788 y(partment)19 b(of)h(Mathematics,)f (Utrecht,)h(The)f(Netherlands,)g(1993.)291 4957 y([190])41 b(B)t(.)27 b(F)m(.)g(S)t FJ(M)t(I)t(T)t(H)r FG(,)c Ft(Domain)d (decomposition)g(algorithms)h(for)i(partial)e(dif)o(fer)m(ential)g (equations)f(of)i(linear)512 5057 y(elasticity)p FG(,)e(T)-6 b(ech.)20 b(Rep.)g(517,)f(Department)g(of)h(Computer)f(Science,)g (Courant)h(Institute,)f(1990.)291 5227 y([191])41 b(P)-5 b(.)23 b(S)t FJ(O)t(N)t(N)t(E)t(V)t(E)t(L)t(D)r FG(,)c Ft(CGS,)g(a)g(fast)h(Lanczos-type)d(solver)j(for)f(nonsymmetric)f (linear)h(systems)p FG(,)h(SIAM)f(J.)512 5327 y(Sci.)i(Statist.)g (Comput.,)e(10)g(\(1989\),)f(pp.)i(36\22652.)291 5497 y([192])41 b(R)t(.)e(S)t FJ(O)t(U)t(T)t(H)t(W)t(E)t(L)t(L)r FG(,)d Ft(Relaxation)c(Methods)h(in)g(Theor)m(etical)g(Physics)p FG(,)k(Clarendon)32 b(Press,)38 b(Oxford,)512 5596 y(1946.)p eop end %%Page: 104 114 TeXDict begin 104 113 bop 739 282 a FG(104)2519 b Fu(BIBLIOGRAPHY)739 515 y FG([193])41 b(H)t(.)28 b(S)t FJ(T)s(O)t(N)t(E)r FG(,)23 b Ft(Iter)o(ative)f(solution)g(of)h(implicit)g(appr)l (oximations)e(of)i(multidimensional)e(partial)h(dif)o(fer)n(-)960 615 y(ential)e(equations)p FG(,)e(SIAM)j(J.)g(Numer)-5 b(.)19 b(Anal.,)h(5)g(\(1968\),)e(pp.)h(530\226558.)739 785 y([194])41 b(P)-5 b(.)24 b(S)t FJ(W)l(A)t(R)t(Z)t(T)t(R)t(AU)t(B)t (E)t(R)r FG(,)e Ft(The)e(methods)e(of)i(cyclic)g(r)m(eduction,)e (Fourier)i(analysis)f(and)g(the)h(F)-10 b(A)n(CR)19 b(algo-)960 885 y(rithm)j(for)g(the)g(discr)m(ete)g(solution)f(of)h(P)-7 b(oisson')m(s)21 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2871 y(and)g(C.Saguez,)g(eds.,)g (North-Holland,)e(1988.)24 b(Also)18 b(as)h(Report)f(No.A-17,)f(Data)h (Processing)g(Center)m(,)960 2971 y(K)n(yoto)h(Uni)n(v)o(ersity)-5 b(,)19 b(K)n(yoto,)g(Japan,)g(December)g(17,)h(1986.)739 3141 y([202])p 960 3128 V 230 w(,)48 b Ft(High)41 b(performance)g(pr)m (econditioning)p FG(,)j(SIAM)e(J.)h(Sci.)f(Statist.)h(Comput.,)j(10)c (\(1989\),)960 3240 y(pp.)20 b(1174\2261185.)739 3410 y([203])p 960 3397 V 230 w(,)h Ft(ICCG)g(and)f(r)m(elated)g(methods)g (for)h(3D)f(pr)l(oblems)h(on)f(vector)g(computer)o(s)p FG(,)g(Computer)f(Physics)960 3510 y(Communications,)24 b(\(1989\),)f(pp.)h(223\226235.)41 b(Also)25 b(as)h(Report)e(No.A-18,)g (Data)h(Processing)f(Center)m(,)960 3610 y(K)n(yoto)19 b(Uni)n(v)o(ersity)-5 b(,)19 b(K)n(yoto,)g(Japan,)g(May)h(30,)g(1987.) 739 3780 y([204])p 960 3767 V 230 w(,)g Ft(The)g(con)m(ver)m(g)o(ence)e (behavior)g(of)i(pr)m(econditioned)d(CG)k(and)e(CG-S)g(in)h(the)g(pr)m (esence)f(of)h(r)l(ound-)960 3879 y(ing)c(err)l(or)o(s)p FG(,)i(in)d(Preconditioned)e(Conjugate)i(Gradient)f(Methods,)i(O.)g(Ax) o(elsson)f(and)g(L.)h(Y)-11 b(.)16 b(K)m(olotilina,)960 3979 y(eds.,)k(v)n(ol.)g(1457)f(of)h(Lecture)f(Notes)i(in)f (Mathematics,)f(Berlin,)h(Ne)n(w)h(Y)-9 b(ork,)19 b(1990,)f(Springer)n (-V)-9 b(erlag.)739 4149 y([205])p 960 4136 V 230 w(,)32 b Ft(Bi-CGST)l(AB:)c(A)h(fast)g(and)g(smoothly)f(con)m(ver)m(ging)f (variant)h(of)h(Bi-CG)g(for)h(the)f(solution)f(of)960 4248 y(nonsymmetric)20 b(linear)g(systems)p FG(,)h(SIAM)f(J.)h(Sci.)g (Statist.)g(Comput.,)e(13)g(\(1992\),)f(pp.)i(631\226644.)739 4418 y([206])41 b(H)t(.)22 b FJ(V)-5 b(A)t(N)23 b(D)t(E)t(R)f FG(V)q FJ(O)t(R)t(S)t(T)g(A)t(N)t(D)h FG(J)t(.)f(M)t FJ(E)t(L)t(I)t(S)t(S)t(E)t(N)r FG(,)c Ft(A)g(Petr)l(o)o(v-Galerkin)f (type)g(method)g(for)h(solving)f FC(Ax)23 b Fy(=)g FC(b)960 4518 y Ft(wher)m(e)e FC(A)g Ft(is)g(symmetric)g(comple)n(x)p FG(,)e(IEEE)h(T)m(rans.)g(Magnetics,)f(26)h(\(1990\),)e(pp.)h (706\226708.)739 4688 y([207])41 b(H)t(.)27 b FJ(V)-5 b(A)t(N)27 b(D)t(E)t(R)g FG(V)q FJ(O)t(R)t(S)t(T)g(A)t(N)t(D)g FG(C)t(.)h(V)t FJ(U)t(I)t(K)r FG(,)23 b Ft(GMRESR:)e(A)i(family)g(of)f (nested)g(GMRES)g(methods)p FG(,)g(T)-6 b(ech.)960 4788 y(Rep.)18 b(91-80,)e(Delft)i(Uni)n(v)o(ersity)f(of)g(T)-6 b(echnology)h(,)15 b(F)o(aculty)j(of)f(T)-6 b(ech.)17 b(Math.,)h(Delft,)g(The)g(Netherlands,)960 4887 y(1991.)739 5057 y([208])41 b(J)t(.)33 b(V)-6 b FJ(A)t(N)33 b FG(R)q FJ(O)t(S)t(E)t(N)t(D)q(A)t(L)t(E)r FG(,)e Ft(Minimizing)d(inner)g(pr)l (oduct)f(data)g(dependencies)f(in)i(conjugate)f(gr)o(adient)960 5157 y(iter)o(ation)p FG(,)20 b(T)-6 b(ech.)19 b(Rep.)h(172178,)e (ICASE,)i(N)m(ASA)h(Langle)o(y)e(Research)h(Center)m(,)f(1983.)739 5327 y([209])41 b(R)t(.)25 b(V)-6 b FJ(A)t(R)t(G)t(A)r FG(,)22 b Ft(Matrix)e(Iter)o(ative)g(Analysis)p FG(,)g(Prentice-Hall)f (Inc.,)h(Engle)n(w)o(ood)e(Clif)n(fs,)i(NJ,)h(1962.)739 5497 y([210])41 b(P)-5 b(.)33 b(V)-6 b FJ(A)t(S)t(S)t(I)t(L)t(E)t(V)t (S)t(K)t(I)r FG(,)30 b Ft(Pr)m(econditioning)25 b(nonsymmetric)i(and)g (inde\002nite)f(\002nite)i(element)g(matrices)p FG(,)i(J.)960 5596 y(Numer)-5 b(.)20 b(Alg.)g(Appl.,)f(1)h(\(1992\),)e(pp.)i (59\22676.)p eop end %%Page: 105 115 TeXDict begin 105 114 bop 291 282 a Fu(BIBLIOGRAPHY)2520 b FG(105)291 515 y([211])41 b(V)-7 b(.)35 b(V)q FJ(O)t(E)t(V)q(O)t(D)t (I)t(N)r FG(,)e Ft(The)e(pr)l(oblem)e(of)h(non-self-adjoint)e(g)o(ener) o(alization)g(of)i(the)g(conjugate)e(gr)o(adient)512 615 y(method)19 b(is)i(closed)p FG(,)f(U.S.S.R.)g(Comput.)f(Maths.)h (and)g(Math.)g(Phys.,)f(23)h(\(1983\),)e(pp.)h(143\226144.)291 781 y([212])41 b(H)t(.)22 b(F)m(.)h(W)-5 b FJ(A)t(L)t(K)t(E)t(R)r FG(,)20 b Ft(Implementation)15 b(of)j(the)g(GMRES)g(method)f(using)g (Householder)f(tr)o(ansformations)p FG(,)512 881 y(SIAM)k(J.)h(Sci.)g (Statist.)g(Comput.,)e(9)h(\(1988\),)e(pp.)h(152\226163.)291 1047 y([213])41 b(P)-5 b(.)25 b(W)t FJ(E)t(S)t(S)t(E)t(L)t(I)t(N)t(G)r FG(,)20 b Ft(An)g(Intr)l(oduction)e(to)j(Multigrid)f(Methods)p FG(,)f(W)m(ile)o(y)-5 b(,)19 b(Chichester)m(,)h(1991.)291 1213 y([214])41 b(O)t(.)25 b(W)t FJ(I)t(D)t(L)t(U)t(N)t(D)r FG(,)e Ft(A)e(Lanczos)g(method)e(for)j(a)f(class)h(of)f(non-symmetric)f (systems)i(of)f(linear)g(equations)p FG(,)512 1312 y(SIAM)f(J.)h(Numer) -5 b(.)20 b(Anal.,)f(15)h(\(1978\),)e(pp.)h(801\226812.)291 1478 y([215])41 b(D)t(.)25 b(Y)r FJ(O)t(U)t(N)t(G)r FG(,)20 b Ft(Iter)o(ative)g(solution)f(of)i(lar)m(g)o(e)f(linear)g(systems)p FG(,)h(Academic)e(Press,)i(Ne)n(w)g(Y)-9 b(ork,)19 b(1971.)291 1644 y([216])41 b(H)t(.)34 b(Y)t FJ(S)t(E)t(R)t(E)t(N)t(T)n(A)t(N)t(T)r FG(,)e Ft(On)e(the)f(multile)o(vel)h(splitting)f(of)h(\002nite)g (element)f(spaces)p FG(,)j(Numer)-5 b(.)29 b(Math.,)i(49)512 1744 y(\(1986\),)18 b(pp.)h(379\226412.)p eop end %%Trailer userdict /end-hook known{end-hook}if %%EOF .