Re: [Bug-gsl] bug in hypergeometric U

[Brian Gough]

Krzysztof Pachucki writes:
 > Dear Brian,
 > the example follows, gsl 1.3:
 > 
 > main()
 > {
 >   double t,gsl_sf_hyperg_U_int();
 >   t =gsl_sf_hyperg_U_int(1,4,0.5); 
 >   printf("16.8f \n",t);
 >         }
 > 
 > gcc bug.c -lgsl -lgslcblas
 > It is the case when U functiopn is a finite series expansion.
 > 

Thanks for the bug report.  A fix is now available in CVS and
attached below.

best regards,
-- 
Brian Gough

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Index: specfunc/gamma.c
===================================================================
RCS file: /cvs/gsl/gsl/specfunc/gamma.c,v
retrieving revision 1.68
retrieving revision 1.69
diff -r1.68 -r1.69
1351c1351,1355
<   if(x < 0.5) {
---
>   if (x <= 0.0 && x == floor(x)) { /* negative integer */
>     result->val = 0.0;
>     result->err = 0.0;
>     return GSL_SUCCESS;
>   } else if(x < 0.5) {