function [out] = randint(varargin); 
%RANDINT Generate matrix of uniformly distributed random integers. 
%   OUT = RANDINT generates a "0" or "1" with equal probability. 
% 
%   OUT = RANDINT(M) generates an M-by-M matrix of random binary numbers. 
%   "0" and "1" occur with equal probability. 
% 
%   OUT = RANDINT(M,N) generates an M-by-N matrix of random binary numbers. 
%   "0" and "1" occur with equal probability. 
% 
%   OUT = RANDINT(M,N,RANGE) generates an M-by-N matrix of random integers. 
% 
%   RANGE can be either a scalar or a two-element vector: 
%   Scalar : If RANGE is a positive integer, then the output integer 
%            range is [0, RANGE-1].  If RANGE is a negative integer, 
%            then the output integer range is [RANGE+1, 0]. 
%   Vector : If RANGE is a two-element vector, then the output 
%            integer range is [RANGE(1), RANGE(2)]. 
% 
%   OUT = RANDINT(M,N,RANGE,STATE) resets the state of RAND to STATE. 
% 
%   Examples: 
%    out = randint(2,3)                out = randint(2,3,4) 
%   out =                              out = 
%        0     0     1                      1     0     3 
%        1     0     1                      2     3     1 
% 
%    out = randint(2,3,-4)             out = randint(2,3,[-2 2]) 
%   out =                              out = 
%       -3    -1    -2                     -1     0    -2 
%       -2     0     0                      1     2     1 
% 
%   See also RAND, RANDSRC, RANDERR. 
 
%   Copyright 1996-2001 The MathWorks, Inc. 
%   $Revision: 1.18 $  $Date: 2001/04/23 15:32:45 $ 
 
 
% Basic function setup. 
error(nargchk(0,4,nargin)); 
 
% --- Placeholder for the signature string. 
sigStr = ''; 
m = []; 
n = []; 
range = []; 
state = []; 
 
% --- Identify string and numeric arguments 
for i=1:nargin 
   if(i>1) 
      sigStr(size(sigStr,2)+1) = '/'; 
   end; 
   % --- Assign the string and numeric flags 
   if(isnumeric(varargin{i})) 
      sigStr(size(sigStr,2)+1) = 'n'; 
   else 
      error('Only numeric arguments are accepted.'); 
   end; 
end; 
 
% --- Identify parameter signitures and assign values to variables 
switch sigStr 
   % --- randint 
   case '' 
 
   % --- randint(m) 
   case 'n' 
      m		= varargin{1}; 
 
	% --- randint(m, n) 
	case 'n/n' 
      m		= varargin{1}; 
      n		= varargin{2}; 
 
	% --- randint(m, n, range) 
	case 'n/n/n' 
      m		= varargin{1}; 
      n  	= varargin{2}; 
      range = varargin{3}; 
 
	% --- randint(m, n, range, state) 
	case 'n/n/n/n' 
      m		= varargin{1}; 
      n		= varargin{2}; 
      range = varargin{3}; 
      state = varargin{4}; 
 
   % --- If the parameter list does not match one of these signatures. 
   otherwise 
      error('Syntax error.'); 
end; 
 
if isempty(m) 
   m = 1; 
end 
if isempty(n) 
   n = m; 
end 
if isempty(range) 
   range = [0, 1]; 
end 
 
len_range = size(range,1) * size(range,2); 
 
% Typical error-checking. 
if (~isfinite(m)) | (~isfinite(n)) 
   error('Matrix dimensions must be finite.'); 
elseif (floor(m) ~= m) | (floor(n) ~= n) | (~isreal(m)) | (~isreal(n)) 
   error('Matrix dimensions must be real integers.'); 
elseif (m < 0) | (n < 0) 
   error('Matrix dimensions must be positive.'); 
elseif (length(m) > 1) | (length(n) > 1) 
   error('Matrix dimensions must be scalars.'); 
elseif len_range > 2 
   error('The RANGE parameter should contain no more than two elements.'); 
elseif max(max(floor(range) ~= range)) | (~isreal(range)) | (~isfinite(range)) 
   error('The RANGE parameter must only contain real finite integers.'); 
end 
 
% If the RANGE is specified as a scalar. 
if len_range < 2 
	 if range < 0 
       range = [range+1, 0]; 
    elseif range > 0 
       range = [0, range-1]; 
    else 
       range = [0, 0];    % Special case of zero range. 
    end 
end 
 
% Make sure RANGE is ordered properly. 
range = sort(range); 
 
% Calculate the range the distance for the random number generator. 
distance = range(2) - range(1); 
 
% Set the initial state if specified. 
if ~isempty(state) 
   rand('state', state); 
end 
 
% Generate the random numbers. 
r = floor(rand(m, n) * (distance+1)); 
 
% Offset the numbers to the specified value. 
out = ones(m,n)*range(1); 
out = out + r; 
 
% [EOF] randint.m