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( #3333=superdoc: print w/ replies, xml )  Need Help?? 
Howdy all, I have a function that I use sometimes when I need permutations (I do permutationtesting often for stats problems). Currently I require the user to pass the "cardinality": how many different elements to put in each class. Let me give a simple example first, before I show the code:
I hope that's reasonably clear: cardinality defines the size of the group I wish to obtain permutations of. The first example above was: all possible pairs of groups of one element. The second example was: all possible pairs of groups of three elements (triplets). Within a single permutation, no element can be repeated, and I take only unique permutations. I am generating all these permutations into a datastructure for later use (e.g. passing them to other software, writing them to file with their results, sending them to a DB, etc.). The code that does this is pretty simple, but unfortunately it has required me to HARDCODE the cardinality. It looks like this:
And so on for higher cardinality. I would prefer to have a generalized way of doing this, rather than needing a separate set of forloops for each cardinality. Is that possible? I'm turned it over in my head, and haven't found a way yet. In reply to Generalizing Code: Generating Unique Permutations by Anonymous Monk

