zhist.m

Lattice coding and decoding

function varargout = zhist(x);

%ZHIST Integer histogram
%   ZHIST(X) plots the histogram of the vector x; x must be all integer
%   vector.
%
%   [Y,Z] = ZHIST(X) returns unique vector Y of vector X; Z is the
%   vector of counts of X.
%
%   [Y,Z,H] = ZHIST(X) same as above, but also gives uniqe vector of
%   histogram values H.
%
%   Example:
%       x = [-1 -1 -2 0 1 1 2 2 3 9 14 23 14 11 31 31 31 22 22 22]';
%       zhist(x)
%       [y,z,h] = zhist(x)
%
%   See also HIST, UNIQUE.

%   Copyright 2001-2003 Kamil Anis, [e-mail]
%   Dept. of Radioelectronics, 
%   Faculty of Electrical Engineering
%   Czech Technical University in Prague
%   $Revision: 0.1 $  $Date: 2003/1/16 17:33:28 $
%   --
%   <additional stuff goes here>

m1 = min(x);
m2 = max(x);
bins = [m1:m2 + 1];

h = hist(x,bins);

x_counts = h(find(h ~= 0))';
x_unique = unique(x);
h_unique = unique(h)';

if nargout == 0
	bar(x_unique,x_counts);
	set(gca,'XTick',x_unique,'YTick',h_unique);
else
	varargout = {x_unique,x_counts,h_unique};
end