function [ res ] = plotTruthFAHistograms( data1, data2, nBins, varargin )
% 
% Written by:
% -- 
% John L. Weatherwax                2006-06-29
% 
% email: wax@alum.mit.edu
% 
% Please send comments and especially bug reports to the
% above email address.
% 
%-----
  
figure; 
 
% Handle all the cases when data1 or data2 is empty:
if( isempty( data1 ) & isempty( data2 ) )
  % Do nothing.
elseif( isempty( data1 ) )
  [ n, x ] = hist( data2, nBins );
  bar( x, n, 'hist', 'r' ); 
elseif( isempty( data2 ) )
  [ n, x ] = hist( data1, nBins );
  bar( x, n, 'hist', 'g' ); 
else

  % Form a matrix with the data:
  amtOfData = max( length(data1), length(data2) );
  histData  = zeros( amtOfData, 2 );
  
  histData(:,1) = [ data1(:).' NaN*ones( 1, amtOfData-length(data1) ) ].';
  histData(:,2) = [ data2(:).' NaN*ones( 1, amtOfData-length(data2) ) ].';
  
  % Plot the data:
  [ n, x ] = hist( histData, nBins );
  bar( x, n(:,1), 'hist', 'g' ); hold on;
  bar( x, n(:,2), 'hist', 'r' ); hold off;

  axis tight;

end

xlabel( 'data value' ); ylabel( 'frequency' );
res = gcf;