Jason, > Does anyone know if it is assumed that if the _pos dictionary in a graph > is not None, then it contains each vertex as a key? It seems like it is > assumed several places in the code (e.g., in the subgraph() function). > However, _pos isn't updated properly (e.g., in the delete_vertex > function, the add_vertex function, etc.). This is leading to bugs in > several other functions. > > If there isn't a policy, then I think we ought to allow _pos to carry > partial information about the graph, i.e., not all vertices have to have > positions specified, if possible.
This was my original assumption, but I and/or others working on the code have probably made the assumption that each vertex was a key from time to time -- this should be fixed. > Also, the _boundary list isn't being updated when vertices are deleted > or a subgraph is made. I can patch this easily, though. +1 Robert L. Miller http://www.rlmiller.org/ --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-devel@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sage-devel URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
