Re: strange behaviour with gsl_cdf_fdist_Q()

[Jason Hooper Stover <jason at sakla dot net>]

This reply bounced the first time out.

On Wed, Sep 03, 2003 at 04:50:54PM -0400, Rajarshi Guha wrote:
> On Wed, 2003-09-03 at 13:04, Rajarshi Guha wrote:
> > Hi,
> >   more problems with gsl_cdf_fdist_Q() and very strange ones at that!
> 
> I've been investigating this problem a little more. 
> 
> I took the code from fdist.c and beta_inc.c and basically renamed the
> functions and compiled the code directly into my binary. Now running my
> program gives different values of P inside the function and absurd
> values of the return value after it has returned from the function!
> 
> With the original gsl_* function from the GSL libs:
> 
> x = 3.145724 nu1 = 7.666667 nu2 = 3.000000 P = 0.044555
> return value = 32.0000
> 
> When I call the renamed funtion in my binary I get
> 
> x = 3.145724 nu1 = 7.666667 nu2 = 3.000000 P = 0.000981
> return value = 521874777.0000
> 
> Assuming that there is a problem somewhere I would have expected that
> whether I called the code from the library or my own program, the
> answers would be consistent.
> 
> Is there some detail of the GSL internals that might lead to this
> difference? I'm still assuming the problem lies in  my code - some form
> of memory corruption somewhere, b ut as soon as I get rid of calls to
> gsl_cdf_fdist_Q(), the program runs fine and produces the expected
> results.

Can you send a copy of the code that shows the problem?

-Jason

> 
> Thanks,
> 
> -------------------------------------------------------------------
> Rajarshi Guha <rajarshi@presidency.com> <http://jijo.cjb.net>
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