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 3 methods: single-vector Lanczos, block Lanczos, and subspace
iteration.  There are 2 implementations of each method (two equivalent
symmetric eigensystems used) for a total of 6 routines.  (M. Berry, U. of Tenn.)

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