Rob Beezer <[email protected]> writes: > I would definitely expect the entries of an undirected graph to just > be 0 and +1 for an incidence matrix. > > Doc string says: > > Returns an incidence matrix of the (di)graph. Each row is a vertex, > and each column is an edge. Note that in the case of graphs, there > is a choice of orientation for each edge.
At least from one point of view it makes sense to make such a choice: when you do, the incidence matrix times it's transpose gives you the Laplace matrix of the graph. Thus if you indeed change this behaviour, it may make sense to add a method that imposes an arbitrary ordering. Martin -- To post to this group, send an email to [email protected] To unsubscribe from this group, send an email to [email protected] For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
