For example: if my values are ['a', 'b', 'c'], then all possible lists of length 2 would be: aa, ab, ac, ba, bb, bc, ca, cb, cc.I created a recursive program to do it, but I was wondering if there was a better way of doing it (possibly with list comprehensions). Here's my recursive version: vals = ['a', 'b', 'c'] def foo(length): if length <=0: return [] if length == 1: return [[x] for x in vals] else: return [x + [y] for x in foo(length - 1) for y in vals]
Sounds like you want one of the combinitoric generators found in itertools[1] -- in this case, the itertools.product() does what you describe. According to the docs, it was added in 2.6 so if you're running an older version, you'd have to back-port it.
-tkc [1] http://docs.python.org/library/itertools.html#itertools.product -- http://mail.python.org/mailman/listinfo/python-list
