comparison toolboxes/FullBNT-1.0.7/KPMstats/multirnd.m @ 0:e9a9cd732c1e tip

first hg version after svn

+function r = multirnd(theta,k)
+%MULTIRND - Random vector from multinomial distribution.
+%   r = multirnd(theta,k) returns a vector randomly selected
+%   from the multinomial distribution with parameter vector
+%   theta, and count k (i.e. sum(r) = k).
+%
+%   Note: if k is unspecified, then it is assumed k=1.
+%
+%   Author: David Ross
+%
+
+%--------------------------------------------------------
+% Check the arguments.
+%--------------------------------------------------------
+error(nargchk(1,2,nargin));
+
+% make sure theta is a vector
+if ndims(theta) > 2 | all(size(theta) > 1)
+    error('theta must be a vector');
+end
+
+% if theta is a row vector, convert it to a column vector
+if size(theta,1) == 1
+    theta = theta';
+end
+
+% make sure k is a scalar?
+
+% if the number of samples has not been provided, set
+% it to one
+if nargin == 1
+    k = 1;
+end
+
+
+%--------------------------------------------------------
+% Main...
+%--------------------------------------------------------
+n = length(theta);
+theta_cdf = cumsum(theta);
+
+r = zeros(n,1);
+random_vals = rand(k,1);
+
+for j = 1:k
+    index = min(find(random_vals(j) <= theta_cdf));
+    r(index) = r(index) + 1;
+end