% 
% Written by:
% -- 
% John L. Weatherwax                2007-07-01
% 
% email: wax@alum.mit.edu
% 
% Please send comments and especially bug reports to the
% above email address.
% 
%-----

clc; close all; 

var_scale = 1;
cA = mvnrnd( [ -4, -2 ], var_scale*eye(2), 20 );
cB = mvnrnd( [ +20.0, +20.0 ], var_scale*eye(2), 20 );
X = [ cA; cB ];

N = size(X,1); 

scatter( X(:,1), X(:,2), 25, ones(N,1), 'filled' );
if( 1 ) saveas( gcf, '../../WriteUp/Graphics/Chapter12/dup_fig_12_2_scatter', 'eps' ); end

s      = 50;  % number of monte-carlo samples to take 
Nsteps = 100; % number of discretization of range [min(d_i,d_j),max(d_i,d_j)] to use 
q      = 40;  % maximum possible number of clusters that can be found in this data set 

[thetas,numFoundClusters] = estimateNumberOfClusters(X,s,Nsteps, q);
plot( thetas, mode( numFoundClusters ), '-' ); 
xlabel('theta'); ylabel('most frequent number of clusters'); 
axis( [ min(thetas), max(thetas), min(mode(numFoundClusters))-1, max(mode(numFoundClusters))+1 ] ); 
if( 1 ) saveas( gcf, '../../WriteUp/Graphics/Chapter12/dup_fig_12_2_num_of_clusters', 'eps' ); end