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From: Greg Heath <heath@alumni.brown.edu>
Newsgroups: comp.soft-sys.matlab
Subject: Re: Ill conditioned matrix makes linsolve crash
Date: Mon, 2 Nov 2009 04:15:30 -0800 (PST)
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On Nov 2, 5:00 am, "Sebastiaan "
<s.breedv...@erasmusmc.REMOVE.BOO.BOO.nl> wrote:
> I am glad to be of some help :)
>
> This bug reminds me of something that happend in 2008a. I think it is this bug as well, but it depended on the runtime of the Matlab session.
>
> My work involves mathematical optimization, in which linear systems are solved hundreds of times for 1 problem. The problem was that in a long batch (~1 day) for solving many problems, Matlab crashed somewhere. However, if I restarted that single problem, Matlab did not crash.
>
> So the bug was reproducable for the long run, on different systems (and maybe I have even tried 2007b). However, the matrix which made Matlab crash, did not crash a fresh session.
>
> I fixed it by checking if the reciprocal condition is sufficient prior to solving the system.
>
> Sebastiaan
>
>
>
> "Bobby Cheng" <bch...@mathworks.com> wrote in message <hcf8jm$9u...@fred.mathworks.com>...
> > I have not done this myself as I can change this from the inside. :)
>
> > But I think you can track the report update and comment of the content.
> > Again, I have not tried any on this.
>
> > I can assure you that it is the same issue in the bug report. I am
> > investigating the issue and have added your matrix into our tests. So thank
> > you for the test case.
>
> > ---Bob

Why not try rcond, backslash and pinv ?

Greg