[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Bug-gsl] testing gsl_log1p when gsl_log1p is not used

From: Brian Gough
Subject: Re: [Bug-gsl] testing gsl_log1p when gsl_log1p is not used
Date: Mon, 23 Jul 2007 22:34:49 +0100
User-agent: Wanderlust/2.14.0 (Africa) Emacs/22.1 Mule/5.0 (SAKAKI)

At Fri, 20 Jul 2007 17:01:04 -0700,
Eugene Loh wrote:
> REQUEST #1: Ruggedize the computation yet further than is already done.  
> E.g.,
> double gsl_log1p (const double x)
> {
>   volatile double y, z;
>   y = 1 + x;
>   z = y - 1;
>   return log(y) - (z-x)/y ;  /* cancels errors with IEEE arithmetic */
> }


Thanks for your email and suggestions.  I will add the correction
above in CVS for the next release.

> REQUEST #2:  Change the check procedures so that unused functions are 
> not tested.  E.g., when you "make check", have sys/test.c test only 
> those gsl_*() functions that will actually be used by GSL.

In this case we're concerned that people can also call the function
gsl_log1p directly, so we always want to test it.  Hopefully your fix
should avoid the problem and make it a moot point in this case.  If
there are any other functions that break, I would like to fix them.

best regards,

Brian Gough
(GSL Maintainer)

Network Theory Ltd,
Publishing the GSL Manual - http://www.network-theory.co.uk/gsl/manual/

reply via email to

[Prev in Thread] Current Thread [Next in Thread]