Christoph Zwerschke wrote: > Now as I'm thinking about it, wouldn't it be nice to have the cartesian > products on Python sets? Maybe also a method that returns the power set > of a set (the set of all subsets), or the set of all subsets with a > given length.
For defining powersets it might suffice to include sets as exponents. If A is a set then Set([0,1])**A is the set of maps from A into {0,1}. The kernels of those maps ( preimages of 0 in A ) is a subset classifier of A. Kay -- http://mail.python.org/mailman/listinfo/python-list