% 
% Written by:
% -- 
% John L. Weatherwax                2005-08-04
% 
% email: wax@alum.mit.edu
% 
% Please send comments and especially bug reports to the
% above email address.
% 
% Epage 169
% 
%-----

close all; clc; clear; 

% Lets draw some decision regions: 
%
x1 = linspace( -2, +2, 50 ); 
x2 = -x1;
plot( x1, x2, 'k-' ); hold on; 
text( -1.3, 1.5, 'x_1 + x_2 = 0' );

addpath('~/Matlab');
hline( 0.25, 'k-' );
text( -1.7, .35, 'x_2 = 1/4' );

x2 = x1;
plot( x1, x2, 'k-' ); 
text( +0.9, 1.5, 'x_1 - x_2 = 0' );

text( -1.75, -1, '(-,-,-)' ); 
text( -1.75,  1, '(-,+,-)' ); 
text( 0,  1, '(+,+,-)' ); 
text( 1.5,  1, '(+,+,+)' ); 
text( -.14,  0.18, '(+,-,-)', 'FontSize', 8 ); 
text( 1.5,  -0.5, '(+,-,+)' ); 
text( 0,  -1, '(-,-,+)' ); 

xlabel('x_1'); ylabel('x_2');

fn = ['chap_4_prob_3_class_regions.eps'];
saveas(gcf,['../../WriteUp/Graphics/Chapter4/',fn],'epsc');