Re: [Bug-gsl] bug in gsl_eigen_hermv

[Brian Gough]

At Sat, 10 Nov 2007 09:05:46 -0700 (MST),
Matthew B. Hastings wrote:
> I think there is a bug in gsl_eigen_hermv which causes it to give nan if
> there ar many very small entries or entries equal to zero.  I checked the
> bug archives, and I found a similar bug report,
> http://lists.gnu.org/archive/html/bug-gsl/2002-10/msg00002.html , for
> gsl-1.2.  However, I am using gsl-1.10.  The bug does not seem to appear
> on gsl-1.4.  I am using Mac OS X 10.4.9 on a PowerPC G4.

Thanks for your bug report.  

It seems to be an architecture dependent problem, I'm not able to
reproduce the NaNs on x86 or x86_64.

Is is possible for you to identify where the NaNs are coming from? e.g
by trapping any division by zero, overflow and invalid operation
exceptions while running under GDB.  The function gsl_ieee_env_setup()
can be used to enable these.

-- 
Brian Gough

Network Theory Ltd,
Publishing Free Software Manuals --- http://www.network-theory.co.uk/