How can I create list of permutations

Question

Hi Everyone,
I need to create a 2 d array which will contain all of the permutations of a 1d input array, specifically, I have a 1 d array of colour boxes and I want to return a 2 d array of colour boxes.  This is too mathematical for me!  Is there a combination of functions that will help me achieve this?  From my days at college I remember something about factorials, but as for coding it...
If anyone has any suggestions I would be very grateful.
Thank you,
Michael.
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Answer 1

Assuming that all colors in the input array are unique, here's a simple algorithm (LabVIEW 8.5). (see also)
The permutation algorithm is from wikipedia:
For every number k, with 0 = k < n!, the following algorithm generates a unique permutation of the initial sequence sj, j = 1, ..., n:
function permutation(k, s) {
     for j = 2 to length(s) {
        swap s[(k mod j) + 1] with s[j]; // note that our array is indexed starting at 1
        k := k / j;        // integer division cuts off the remainder
     return s;
NOTE: Indexing in LabVIEW starts at 0, so the code is changed accordingly.
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