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Re: test release gsl-1.8.90.tar.gz
On Fri, Feb 16, 2007 at 09:25:30PM +0000, Brian Gough wrote:
> At Fri, 16 Feb 2007 00:09:34 -0800,
> Tim Fenn wrote:
> > I've been testing the bfgs2 minimizer, and it works well until/if it
> > nears a point in which the interpolator stops progressing - I've
> > noticed there is a check against this in the linear_minimize code near
> > line 209:
> >
> > if ((a-alpha)*fpa <= GSL_DBL_EPSILON) {
> > /* roundoff prevents progress */
> > };
> >
> > perhaps there should be a break statement to prevent futile
> > iterations? Or use this as a stopping criteria test?
>
> Thanks, there should be a
>
> return GSL_ENOPROG;
>
> in there. You might want to try that and see if it stops at an
> acceptable place.
That helps, yes. It also might be worthwhile to note the bfgs2
minimizer requires positive step_size values (which makes intuitive
sense, but is not true of the bfgs/cgpr/cgfr minimizers).
Regards,
Tim
--
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Tim Fenn
fenn@stanford.edu
Stanford University, School of Medicine
James H. Clark Center
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Stanford, CA 94305-5432
Phone: (650) 736-1714
FAX: (650) 736-1961
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