Can anyone improve my program for generate permutations??

 a = [20 20 20 20 20 20 10 10 10 10];

 a1 = unique(a);

 a2 = perms([a1,fliplr(a1), a1]);

 p1 = [a2 , fliplr(a2),a2 , fliplr(a2), a2];

 p2 = p1 (:, 1:length(a));

 ppp = unique(p2,'rows');

 threshold = 2;
 ppp( sum(ismember(ppp, a1), 2) < threshold, :) = [];

 pp = permute(ppp, [3 2 1]);

I want to generate more permutations. Increase variations of theta. i want to make sequence like this...

 [20 20 10 10 10 10 10 10 10 10] %only two theta's of 20. means change nos of theta

 [ 20 20 20 10 10 10 10 10 10 10]
 [10 10 20 20 20 20 20 20 20 20] and so on...unique theta is not less than 2....

Answer 1

[Walter Roberson]

http://uk.mathworks.com/matlabcentral/answers/269039-how-to-generate-permutations-by-increase-or-decrease-no-of-unique-values#comment_344111