1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
|
function [Y,index] = Shuffle(X)
% [Y,index] = Shuffle(X)
%
% Randomly sorts X.
% If X is a vector, sorts all of X, so Y = X(index).
% If X is an m-by-n matrix, sorts each column of X, so
% for j=1:n, Y(:,j)=X(index(:,j),j).
%
% Also see SORT, Sample, Randi, and RandSample.
% xx/xx/92 dhb Wrote it.
% 10/25/93 dhb Return index.
% 5/25/96 dgp Made consistent with sort and "for i=Shuffle(1:10)"
% 6/29/96 dgp Edited comments above.
% 5/18/02 dhb Modified code to do what comments say, for matrices.
% 6/2/02 dhb Fixed bug introduced 5/18.
[null,index] = sort(rand(size(X)));
[n,m] = size(X);
Y = zeros(size(X));
if (n == 1 | m == 1)
Y = X(index);
else
for j = 1:m
Y(:,j) = X(index(:,j),j);
end
end
|
