On Wed, 22 Aug 2018 at 00:44, Poul Riis <prii...@gmail.com> wrote: > > I would like to list all possible ways to put N students in groups of k > students (suppose that k divides N) with the restriction that no two students > should ever meet each other in more than one group. > I think this is a classical problem and I think there must be a python > solution out there but I cannot find it. For instance, numpy's array_split > only lists one (trivial) split. > I would be happy if someone could refer me to a general python algorithm > solving the problem.
The basic problem seems to be a simple case of looking for combinations of k items from N, which is something itertools can help you with. I don't understand the restriction (or at least, if I understand the basic requirement then the restriction makes no sense to me, as a set of combinations only puts any one student in one group, so "meeting someone in more than one group" isn't possible). But what I'd be inclined to do, at least as a first approach (refine it if it's too slow for your real case) is to take each basic solution, and check if it satisfies the extra constraint - keep the ones that do. Combinatorial problems typically grow very fast as N (and/or k) increase, so that approach may not work as a practical solution, but it will at least mean that you code your requirement in an executable form (which you can test for small numbers) and then you'll have a more precise problem to describe when looking for help tuning it. Paul -- https://mail.python.org/mailman/listinfo/python-list
