%
% An extension of Example 9.3
% This shows how to get the quartiles using Tukey's method.
% 
% Written by:
% -- 
% John L. Weatherwax                2005-08-14
% 
% email: wax@alum.mit.edu
% 
% Please send comments and especially bug reports to the
% above email address.
% 
%-----

close all; drawnow; 
rehash; 
clc; 
clear; addpath( '../../Code/eda_data' ); addpath( '../../Code/eda_toolbox' ); addpath( '../Chapter1' ); 
addpath( '../../../CSHWM/Code/CSTool/' ); % <- for cshistden.m 

load geyser; n = length( geyser ); 

p = [ 0.25, 0.75 ];
for pi=1:length(p), 
  fprintf( 'quantile ( %10.6f ) geyser = %10.6f\n', p(pi), quantile( geyser, p(pi) ) );
end

figure; boxplot( geyser ); 
title( 'geyser data boxplot' );

% use the normal-reference rule to determine bin widths / number of bins: 
st  = std(geyser); 
hNR = (24*(st^(3))*sqrt(pi) / n )^(1/3); 
N   = ceil( (max(geyser)-min(geyser))/hNR ); 

figure; cshistden( geyser, N );