SVDPACK is a Fortran-77 library of subroutines for computing the singular
values and singular vectors of large sparse matrices.  The current library
consist of 4 methods: single-vector Lanczos, block Lanczos, subspace iteration,
and trace-minimization.  Two implementations of each method (two equivalent
symmetric eigensystems) are included (8 routines).      (M. Berry, U. of Tenn.)

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