MATLAB Answers


How to make combinations of given condition?

Asked by C Zeng on 28 Dec 2012

Hi, all,

For example, if I want to make all combination of 5-dim vectors have only 2 two's, other entries are all 0. Is there a command in Matlab can do it? That is 22000 20200 20020 20002 02200 02020 02002 00220 00202 00022



Log in to comment.

2 Answers

Answer by Andrei Bobrov
on 28 Dec 2012
Edited by Andrei Bobrov
on 28 Dec 2012
 Accepted Answer

k = dec2bin(0:sum(pow2(0:4)))-'0';
out = 2*k(sum(k,2) == 2,:);

  1 Comment

Andrei, thanks, can you explain?

Actually I want all other entries to be 1. Is there a way to do it easily?

I tried your code, it works here though not understood here. :-(

Log in to comment.

Answer by Roger Stafford on 28 Dec 2012

This is a problem for matlab's 'nchoosek' function.

  1 Comment

Log in to comment.

Discover what MATLAB® can do for your career.

Opportunities for recent engineering grads.

Apply Today

Win prizes and improve your MATLAB skills

Play today