matlab - How to calculate cyclic permutation of an array? -

how calculate cyclic permutation of array easy [ 1 2 3 4 ] in matlab . there function can directly compute circular permutation in matlab .

i'm assuming cyclic permutation mean this (1 2 3 4 considered same permutation cyclic shift 2 3 4 1; want permutations different cyclic shift of each other):

one possible approach generate permutations, identify circularly equal, , keep 1 each group. done keeping permutations begin given index, example 1. follows problem can solved generating permutations of elements 2, 3, ... , attaching element 1 in front:

x = [ 1 2 3 4 ]; %// data  p = perms(x(2:end)); %// generate permutations of x(2), x(3), ... p = [ repmat(x(1),size(p,1),1) p ]; %// attach x(1) in front of each permutation 

in example, result is:

p =      1     2     3     4      1     2     4     3      1     3     2     4      1     3     4     2      1     4     2     3      1     4     3     2 

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or, if mean this (you want generate permutations cyclic shifts of each other: 1 2 3 4, 2 3 4 1, etc; 1 3 2 4 not allowed):

x = [ 1 2 3 4 ]; %// data  n = numel(x); ii = mod(bsxfun(@plus, 1:n, (0:n-1).')-1, n) + 1; p = x(ii); 

result:

p =      1     2     3     4      2     3     4     1      3     4     1     2      4     1     2     3