2 #include <gsl/gsl_errno.h>
3 #include <gsl/gsl_sf_bessel.h>
11 double expected = -0.17759677131433830434739701;
13 int status = gsl_sf_bessel_J0_e (x, &result);
15 printf ("status = %s\n", gsl_strerror(status));
16 printf ("J0(5.0) = %.18f\n"
18 result.val, result.err);
19 printf ("exact = %.18f\n", expected);