Re: Meschach - SVD on a sparse matrix

On 2007-07-13 00:39:46 +0200, "akakiyakakievich@xxxxxxxxx" <akakiyakakievich@xxxxxxxxx> said:

Hi,

I'm trying use meschach, compiling some programs, etc. because I need
compute svd on a sparse matrix.
http://www.netlib.org/c/meschach/
http://www.math.uiowa.edu/~dstewart/meschach/
Reading the FAQ:
"A1. What is Meschach?........
......o eigenvector/eigenvalue routines -- symmetric, real Schur
decomposition, SVD, extract eigenvector....."

"A2. Why not use C versions of LINPACK, EISPACK or LAPACK?.......
.....
As well, none of the above packages has anything to do with sparse
matrices. There are, of course, sparse matrix packages that are
freely
available, but even there, they do not seem to handle, in an
integrated
way, both sparse and dense matrices. Meschach has not only sparse
matrix
data structures and the routines to make use of them, but as the
sparse
matrices are self-contained data structures, use of sparse and dense
matrices can be intermixed...."

But, when I look for svd function, I only get in matrix2.h/svd.c,

svd.c:VEC *svd(MAT *A, MAT *U, MAT *V, VEC *d)

MAT (dense matrix) implementation but not the SPMAT (sparse matrix)

It seems that don't have svd functionality for SPMAT, I've seen
samples in tutorial.c, torture.c and ztorture.c. Only has used SPMAT
in tutorial.c /* discrete laplacian */ SPMAT *laplacian(A) SPMAT *A
function.



Anyone has used meschach for svd on a sparse matrix? other package?
suggestions?

Thanks in advance!
A

Did you have a look at http://www.netlib.org/svdpack/ ?

Michael


.

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