function [ n_data, x, fx ] = bessel_y0_int_values ( n_data ) %% BESSEL_Y0_INT_VALUES returns some values of the Bessel Y0 integral. % % Discussion: % % The function is defined by: % % Y0_INT(x) = Integral ( 0 <= t <= x ) Y0(t) dt % % The data was reported by McLeod. % % Modified: % % 30 August 2004 % % Author: % % John Burkardt % % Reference: % % Allan McLeod, % Algorithm 757, MISCFUN: A software package to compute uncommon % special functions, % ACM Transactions on Mathematical Software, % Volume 22, Number 3, September 1996, pages 288-301. % % Parameters: % % Input/output, integer N_DATA. The user sets N_DATA to 0 before the % first call. On each call, the routine increments N_DATA by 1, and % returns the corresponding data; when there is no more data, the % output value of N_DATA will be 0 again. % % Output, real X, the argument of the function. % % Output, real FX, the value of the function. % n_max = 20; fx_vec = [ ... -0.91442642860172110926E-02, ... -0.29682047390397591290E-01, ... -0.25391431276585388961E+00, ... -0.56179545591464028187E+00, ... -0.63706937660742309754E+00, ... -0.28219285008510084123E+00, ... 0.38366964785312561103E+00, ... -0.12595061285798929390E+00, ... 0.24129031832266684828E+00, ... 0.17138069757627037938E+00, ... 0.18958142627134083732E+00, ... 0.17203846136449706946E+00, ... -0.16821597677215029611E+00, ... -0.93607927351428988679E-01, ... 0.88229711948036648408E-01, ... -0.89324662736274161841E-02, ... -0.54814071000063488284E-01, ... -0.94958246003466381588E-01, ... -0.19598064853404969850E-01, ... -0.83084772357154773468E-02 ]; x_vec = [ ... 0.0019531250E+00, ... 0.0078125000E+00, ... 0.1250000000E+00, ... 0.5000000000E+00, ... 1.0000000000E+00, ... 2.0000000000E+00, ... 4.0000000000E+00, ... 6.0000000000E+00, ... 10.0000000000E+00, ... 16.0000000000E+00, ... 16.2500000000E+00, ... 17.0000000000E+00, ... 20.0000000000E+00, ... 25.0000000000E+00, ... 30.0000000000E+00, ... 40.0000000000E+00, ... 50.0000000000E+00, ... 70.0000000000E+00, ... 100.0000000000E+00, ... 125.0000000000E+00 ]; if ( n_data < 0 ) n_data = 0; end n_data = n_data + 1; if ( n_max < n_data ) n_data = 0; x = 0.0; fx = 0.0; else x = x_vec(n_data); fx = fx_vec(n_data); end