These are chat archives for elemental/chat

30th
Jan 2017
Ryan H. Lewis
@rhl-
Jan 30 2017 11:53
Thanks :)
Jack Poulson
@poulson
Jan 30 2017 16:16
@AidanGG Sorry, I hadn't checked this gitter in a while for temporary reasons. The COMPACT_SVD is indeed meant to have that behavior: the finite-precision reduction to bidiagonal form introduces a perturbation of magnitude similar to eps || A ||_2 max(m,n), and so one should ignore singular values below this amount.
any cases of SVD not converging should be a bug: do you have a reproducing example?
there are several SVD algorithms (e.g., Divide and Conquer and QR), so it is unlikely that multiple of them are not converging for the same matrix
and you are correct that ScaLAPACK does not support 64-bit integers (and the problem is in the library itself, not Elemental)
I've been working on getting the LP solvers to work on all of the http://www.netlib.org/lp/data/ examples using a symmetric-indefinite solver and hadn't been checking in as much as I should have