# Specific pseudo-randomised number generator.

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Matt W on 18 Sep 2019
Commented: Bruno Luong on 19 Sep 2019
I am currenlty running an experiment that reads from a text file that requires specific formatting.
I need to create a matrix composed to two colunms (e.g. 200 x 2). One column needs to consist of only 1's and -1's in a pseudorandomised order with no more than three repeats of the same number consequatively and each number to appear an equal amount of times. The other column needs to be composed of 0's and 1's, where the 1's match up with the 1's in the first column and the 0's match up with the -1's.
I was wondering if this would be simple to do in Matlab and/or if anyone could help me out?
Cheers.

Bruno Luong on 19 Sep 2019
Edited: Bruno Luong on 19 Sep 2019
n = 2*ones(2,50);
for k=1:2
p=randperm(50,32); % you might randomize 32 as well (must be even number in [0,50]);
n(k,p)=repmat([1 3],1,length(p)/2);
end
A=repelem(repmat([-1 0; 1 1],50,1),n(:),1)

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Bruno Luong on 19 Sep 2019
32=2*16
Meaning I want to generate 16 sequence of 1-length, 16 sequences of 3-length and then 18 (=50-32) sequences of 2-length (so the total length of all sequences is 100).
If you reduce the parameter 32 you'll have more sequences of length 2 than 1 and 3. And vice versa.
Matt W on 19 Sep 2019
Great, thank you. Last thing; I then assume that if I require additional rows (e.g. 400 rather than 200) I would change the 50 to 100 and would need to adjust the parameter 32 accordingly e.g. 64 or 66?!
Thanks.
Bruno Luong on 19 Sep 2019
Correct.