function [ n_data, x, fx ] = cin_values ( n_data ) %*****************************************************************************80 % %% CIN_VALUES returns some values of the alternate cosine integral function. % % Discussion: % % The alternate cosine integral is defined by % % CIN(X) = gamma + log(X) + integral ( 0 <= T <= X ) ( cos ( T ) - 1 ) / T dT % % In Mathematica, the function can be evaluated by: % % EulerGamma + Log[x] - CosIntegral[x] % % Licensing: % % This code is distributed under the GNU LGPL license. % % Modified: % % 16 September 2004 % % Author: % % John Burkardt % % Reference: % % Milton Abramowitz and Irene Stegun, % Handbook of Mathematical Functions, % US Department of Commerce, 1964. % % Stephen Wolfram, % The Mathematica Book, % Fourth Edition, % Wolfram Media / Cambridge University Press, 1999. % % 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 = 16; fx_vec = [ ... 0.6185256314820045E-01, ... 0.8866074809482194E-01, ... 0.1200260139539026E+00, ... 0.1557934976348559E+00, ... 0.1957873187759337E+00, ... 0.2398117420005647E+00, ... 0.3390780388012470E+00, ... 0.4516813164280685E+00, ... 0.5754867772153906E+00, ... 0.7081912003853150E+00, ... 0.8473820166866132E+00, ... 0.1207635200410304E+01, ... 0.1556198167561642E+01, ... 0.1862107181909382E+01, ... 0.2104491723908354E+01, ... 0.2274784183779546E+01 ]; x_vec = [ ... 0.5E+00, ... 0.6E+00, ... 0.7E+00, ... 0.8E+00, ... 0.9E+00, ... 1.0E+00, ... 1.2E+00, ... 1.4E+00, ... 1.6E+00, ... 1.8E+00, ... 2.0E+00, ... 2.5E+00, ... 3.0E+00, ... 3.5E+00, ... 4.0E+00, ... 4.5E+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 return end