bug-gsl
[Top][All Lists]
Advanced

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

[Bug-gsl] Fwd: Error estimate in hyperg_U


From: Raymond Rogers
Subject: [Bug-gsl] Fwd: Error estimate in hyperg_U
Date: Mon, 25 Oct 2010 19:51:49 -0500
User-agent: Mozilla/5.0 (X11; U; Linux i686 (x86_64); en-US; rv:1.9.2.11) Gecko/20101013 Thunderbird/3.1.5

Below is a program demonstrating what I think is a bogus error estimate for gsl_sf_hyperg_U_e(4.111,.11,6.4)
The output with gsl 1.14 is:
Values a0,a1,a2,b,x 4.109000e+00, 4.110000e+00, 4.111000e+00 1.100000e-01, 6.400000e+00 Values hyperg_U_e result.val = 6.439287e-05, 6.422378e-05, 6.405513e-05 Error return hyperg_U_e result.err= 1.217053e-18, 6.422378e-05, 1.224921e-18
hyperg_U = 6.422378e-05



Ray


____________________________________
#include <stdio.h>
#include <gsl/gsl_sf_hyperg.h>
//#include <gsl/gsl_sf_result.h>

#include <complex.h>



     int
     main (void)
     {
    double a1=4.11;double a2=4.111;double a0=4.109;
    double b=0.11;
       double  x = 6.4;
    printf("Values a0,a1,a2,b,x\t\t%e,\t%e,\t%e \t%e,\t%e\n",a0,a1,a2,b,x);
     gsl_sf_result   result0,result1,result2;
     double y= gsl_sf_hyperg_U (a1,b,x);
     int ye0=gsl_sf_hyperg_U_e(a0,b,x, &result0);
    int ye1=gsl_sf_hyperg_U_e(a1,b,x, &result1);
    int ye2=gsl_sf_hyperg_U_e(a2,b,x, &result2);
       printf ("hyperg_U = %e\n",y);
printf("Values hyperg_U_e_val = \t%e,\t%e,\t%e\n",result0.val ,result1.val,result2.val); printf("Error return hyperg_U_e_val = \t%e,\t%e,\t%e\n",result0.err ,result1.err,result2.err);
       return 0;
     }
_______________________________________


reply via email to

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