# Create 9x9 matrix with RANDI between [0,2] with each 0,1, and 2 repeating three times each per column.

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Ryan Graham on 23 Sep 2020
Edited: Abdolkarim Mohammadi on 23 Sep 2020
I'm trying to create a 9x9 matrix with random number generation from 0 to 2 using RANDI:
X = randi([0,2], 9,9)
However, I want to force each of the 9 columns to show an equal distribution of 0's, 1's, and 2's (3 x of each number per column). I'm having difficulty finding a loop that can do this. Any help would be great (very new to this type of MATLAB work).
Thanks.

Abdolkarim Mohammadi on 23 Sep 2020
Edited: Abdolkarim Mohammadi on 23 Sep 2020
You can first create a vector with the values you need:
Reference = repelem (0:2,3)';
Then you initialize the 9x9 matrix with zeros(), and finally fill in the columns with random permutations of Reference using randperm().
Abdolkarim Mohammadi on 23 Sep 2020
Edited: Abdolkarim Mohammadi on 23 Sep 2020
Yes. But the number of rows should not change. For example: zeros (9,4). Otherwise, you should update Reference have the same number of elements as the number of rows in M.

### More Answers (1)

Bruno Luong on 23 Sep 2020
Edited: Bruno Luong on 23 Sep 2020
[~,A] = sort(rand(9)); A = mod(A,3)