public static void bessel_y1_values_test()
    //****************************************************************************80
    //
    //  Purpose:
    //
    //    BESSEL_Y1_VALUES_TEST tests BESSEL_Y1_VALUES.
    //
    //  Licensing:
    //
    //    This code is distributed under the GNU LGPL license.
    //
    //  Modified:
    //
    //    02 March 2007
    //
    //  Author:
    //
    //    John Burkardt
    //
    {
        double fx = 0;
        double x  = 0;

        Console.WriteLine("");
        Console.WriteLine("BESSEL_Y1_VALUES_TEST:");
        Console.WriteLine("  BESSEL_Y1_VALUES stores values of ");
        Console.WriteLine("  the Bessel Y1 function.");
        Console.WriteLine("");
        Console.WriteLine("                X                   Y1(X)");
        Console.WriteLine("");
        int n_data = 0;

        for (;;)
        {
            Bessel.bessel_y1_values(ref n_data, ref x, ref fx);
            if (n_data == 0)
            {
                break;
            }

            Console.WriteLine("  "
                              + x.ToString("0.################").PadLeft(24) + "  "
                              + fx.ToString("0.################").PadLeft(24) + "");
        }
    }