dear pythonistas, So imagine that we have a set of sets S. If we pick arbitrarily one set, s0, what are all the combinations of other sets in S which when combined by set operations result in s0?
s0 = set([1]) s1 = set([1,2]) s2 = set([2]) S = set([s0,s1,s2]) one answer we're searching for is s0 = s1 - s2 There may be arbitrarily many set elements (denoted by integers 1,2,3,...) and arbitrarily many combinations of the elements composing the sets s_i (s0, s1, ...). We can use any operation or function which takes and returns sets. I think this problem is related to integer partitioning, but it's not quite the same. The range of answers has a little combinatorial explosion problem as S gains new members. In my problem, len(S) is usually on the order of 1M, and in the worst case, 10M, and there are on the order of 10k elements. My attempts to come up with an algorithm have not succeeded. Any ideas occur to you folks? -- PB. -- Patrick Ball, Ph.D. Chief Scientist & Director, Human Rights Program http://www.benetech.org http://www.hrdag.org http://www.martus.org -- http://mail.python.org/mailman/listinfo/python-list
