How to run randperm command for 100 times and store these permutations

Hi, I want to run randperm command to generate different permutations and save these permutation . The following code oly shows the last permutation. k contains only one permutation

N=10;T=4;
k=zeros(10,4);
for ii=1:T-1
Z = arrayfun(@(x)randperm(N),ii,'UniformOutput',0);
Z = cell2mat(Z);
k=Z;
end

Answer 1

[Voss]

To save each permutation, assign it to a row or column of k, instead of overwriting k each time.

You've set up k to have 10 rows for permutations of length 10, so it looks like you want each permutation to be a column of k:

N=10;T=4;
% k=zeros(10,4);
k=zeros(N,T);
for ii=1:T-1
%     Z = arrayfun(@(x)randperm(N),ii,'UniformOutput',0);
%     Z = cell2mat(Z);
    Z = randperm(N); % this does the same thing as the two lines above
    k(:,ii)=Z;
end
k

k = 10×4

1 4 5 0 2 3 1 0 6 9 6 0 5 8 7 0 4 1 4 0 10 6 3 0 8 10 2 0 9 7 8 0 7 2 9 0 3 5 10 0

You can make each permutation be a row of k instead (here making T permutations instead of T-1):

N=10;T=4;
k=zeros(T,N);
for ii=1:T
    k(ii,:)=randperm(N);
end
k

k = 4×10

10 5 9 1 7 8 4 2 3 6 10 4 9 5 3 2 1 8 7 6 2 9 8 1 5 6 4 3 7 10 7 9 3 2 10 6 1 8 4 5

And this type of thing may have been what you were going for with arrayfun/cell2mat:

N=10;T=4;
k = cell2mat(arrayfun(@(x)randperm(N),1:T-1,'UniformOutput',0).')

k = 3×10

1 2 5 3 8 4 6 10 7 9 2 7 3 8 6 9 1 10 4 5 3 2 8 1 10 7 6 9 5 4

[lilly lord]

Thanks for your help Sir.

[Voss]

You're welcome!