>> I also wondered whether you wanted to compute isomorphisms in which the >> two sets are exchanged > I think both questions make sense, depending on the problem you're > working with.
Indeed. That's why I think that such code should be "custom code", code that you write for yourself and that just creates more problems than it solves when added to a library like Sage. Like the merge_vertices* things and all its loops/multiedges problems :-P > Maybe the default should be to consider purely the > partition, BipartiteGraph(1,0) should be isomorphic to > BipartiteGraph(0,1). But there are certainly cases where you would > require the first bipartite set of the first graph to be mapped to the > first bipartite graph of the second graph, or even cases in which you > *require* the bipartite sets to be swapped. Yep. I had this problem pretty recently. I added a vertex adjacent to all vertices on the left set (its degree was then higher than any other vertex in my graph) and computed theisomorphism with this graph :-) Nathann -- -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
