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- To: eigen@xxxxxxxxxxxxxxxxxxx
- Subject: Re: [eigen] SVD Bug
- From: Benoit Jacob <jacob.benoit.1@xxxxxxxxx>
- Date: Thu, 23 Sep 2010 07:43:58 -0400
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I confirm that before your patch, valgrind finds a lot of errors in
his testcase, and that they are all gone with your patch.
Now looking at the unit test...
Of course we must maintain the current SVD implementation until we
replace it with something better.
2010/9/23 Hauke Heibel <hauke.heibel@xxxxxxxxxxxxxx>:
> the user chef_seppel has found a bug in the SVD. Here is the post
> http://forum.kde.org/viewtopic.php?f=74&t=90425. I can confirm it is a
> In principle, the attached patch should fix it. I also changed the
> unit test and according to our docs
> (http://eigen.tuxfamily.org/dox/classEigen_1_1SVD.html) I would expect
> any m-by-n matrix A to be working (when m>n). But the unit test fails
> even for the most simple example where A is 3-by-2, x is 2-by-1 and b
> is 3-by-1. The failure is caused by the solve part.
> I tried to look into it but failed. I can only say that already the
> matrix U is strange since its last row is zero and this should not be
> the case.
> I know that Benoit is still working on rewriting the SVD but at least
> the bad memory access should be fixed.