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From: Brian Gough <bjg@network-theory.co.uk>
To: Devin Balkcom <devin@ri.cmu.edu>
Cc: gsl-discuss@sources.redhat.com
Subject: Re: SVD bugs in gsl version .9.1?
Date: Wed, 19 Dec 2001 13:20:00 -0000	[thread overview]
Message-ID: <15244.5395.985031.513235@debian> (raw)
In-Reply-To: <3B8BE5C9.FA9DE2F@ri.cmu.edu>

Devin Balkcom writes:
 > I'm using gsl to take singular value decompositions.  I have had
 > problems with all three of the
 > implementations.   I have written a test program.
 > 
 > - gsl_linalg_SV_decomp() does not return for the test matrix.
 > - gsl_linalg_SV_decomp_mod() also does not return.
 > - gsl_linalg_SV_decomp_jacobi() does return, although I have had it fail
 > in other circumstances,
 >     with an incorrect result.  (I will send test code for this case
 > later.)

Thanks for the bug report.  

It is a bug in the SVD.... which is not handling the 2x2 case [0,X;0,0]
correctly, so it never converges for that matrix. I'll fix that.

regards
Brian Gough

  reply	other threads:[~2001-12-19 13:20 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2001-12-19 13:20 Devin Balkcom
2001-12-19 13:20 ` Brian Gough [this message]
2001-12-19 13:20   ` Brian Gough
     [not found]     ` <000b01c13115$f384b780$ad96f88f@sghong>
2001-12-19 13:20       ` GSL for MSVC++ (Warning message report) Brian Gough
2001-12-19 13:20         ` Brian Gough

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