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Re: bugs(s) in specfunc



You're right. I just committed the fixes to CVS.

Thanks.

-- 
G. Jungman


Thomas Walter wrote:
> 
> Hello,
> while writing some interface functions between 'octave' and 'gsl' I
> think I found a few bugs.
> 
> The files 'gsl_sf_coulomb.h' and 'coulomb.c' seem out of sync.
> The header file declares
>     int gsl_sf_coulomb_wave_FGp_impl()
> and the source file defines
>     int
>     gsl_sf_coulomb_wave_FGp_array_impl()
> 
> The file 'log.c' defines the functions
>     int
>     gsl_sf_log_1plusx_impl()
> and
>     int
>     gsl_sf_log_1plusx_mx_impl()
> I think the used series expansion for small x
>   if(fabs(x) < GSL_ROOT5_DBL_EPSILON)
> has the wrong sign for the constant 'c6'.
> 
> Also the series seems too short to fill a 'double' with valid digits.
> You can verify this especially for 'gsl_sf_log_1plusx_mx_impl()' if
> you call this function with values near the border
> 'GSL_ROOT5_DBL_EPSILON'.  I suggest to extend the series at least with
> the constants 'c7 = -1/8' and 'c8 = 1/9'.
> 
> Bye
> Thomas
> 
> --
> Warum hat eine Leiterbahn keine 90 Grad Winkel sondern 2 mal 45 Grad?
> Weil die Elektronen sonst immer gegen die Wand laufen 8-)))
> 
> ----------------------------------------------
> Dipl. Phys. Thomas Walter
> Inst. f. Physiklische Chemie II
> Egerlandstr. 3                          Tel.: ++9131-85 27326 / 27330
> 91058 Erlangen, Germany                 email: walter@pctc.chemie.uni-erlangen.de

-- 
G. Jungman

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