problem in gsl_sf_bessel_Jn

[Arvid Requate <arvid at Mathematik dot Uni-Bielefeld dot DE>]

Hi,

there seem to be problems within gsl_sf_bessel_Jn and gsl_sf_bessel_Jn_array:
 - for n<168 they do not return exactly the same results.
 - for n=168 only gsl_sf_bessel_Jn returns successfull
 - for n>168 both routines return with errors (e.g. in airy.c)

some example code (c++) is attached.
Kind regards
	Arvid Requate

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#include "gsl/gsl_sf.h"
#include "stream.h"


main(){
    int Nmin = 0;
    int Nmax=167;
    double data[Nmax-Nmin+1], arg, x;

    arg = 1.88;

    gsl_sf_bessel_Jn_array(Nmin, Nmax, arg, data);
    for (int i = 0; i <= Nmax; ++i) {
	x=gsl_sf_bessel_Jn(i, arg);
	cout << "Jn:       " << i << "  " << x << endl;
	cout << "Jn_array: " << i << "  " << data[i] << endl;
	cout << "Difference: " << "  " << data[i] - x << endl;
    }

    x=gsl_sf_bessel_Jn(Nmax+1, arg);
    cout << "Jn:       " << Nmax+1 << "  " << x << endl;
    double data2[Nmax-Nmin+2];
    gsl_sf_bessel_Jn_array(Nmin, Nmax+1, arg, data2);
    cout << "Jn_array: " << Nmax+1 << "  " << data[Nmax+1] << endl;
    cout << "Difference: " << "  " << data[Nmax+1] - x << endl;
}