%
% Written by:
% --
% John L. Weatherwax                2009-04-21
%
% email: wax@alum.mit.edu
%
% Please send comments and especially bug reports to the
% above email address.
%
%-----

addpath('../../BookCode');

close all; clc; clear; 

% EPage 137

x = 0:0.1:1;
y = gamma( x + 1 );

plot( x, y, '.', 'MarkerSize', 18 ); hold('on');

pp = polyfit( x, y, 5 )
xx = linspace( 0, 1, 100 );
yy = polyval( pp, xx );

plot( xx, yy, '-b' );

a0 = 1;
a1 = -0.5748666;
a2 = 0.9512363;
a3 = -0.6998588;
a4 = 0.4245549;
a5 = -0.1010678;

y_Abramowitz_N_Stegun = a0 + a1 * xx + a2 * xx.^2 + a3 * xx.^3 + a4 * xx.^4 + a5 * xx.^5; 
plot( xx, y_Abramowitz_N_Stegun, '-g' ); 

legend( 'data', 'fifth degree poly', 'Abramowitz/Stegun', 'location', 'best' );

%saveas( gcf, '../../WriteUp/Graphics/Chapter7/c_7_p_9_plot.eps', 'epsc' );