#include <stdio.h>

#include <gsl/gsl_errno.h>

#include <gsl/gsl_sf_bessel.h>

int

main (void)

{

  double x = 5.0;

  gsl_sf_result result;

  double expected = -0.17759677131433830434739701;

  int status = gsl_sf_bessel_J0_e (x, &result);

  printf ("status  = %s\n", gsl_strerror(status));

  printf ("J0(5.0) = %.18f\n"

          "      +/- % .18f\n", 

          result.val, result.err);

  printf ("exact   = %.18f\n", expected);

  return status;

}