I'm trying to add the needed functions to make one of our graphs work as a boost graph and ran into a contradiction in the docs:
The introduction to bidirectional graph says
"For
undirected graphs this [need for extra information] is not an issue, since the in_edges()
and out_edges() functions are the same, they both return the
edges incident to the vertex."
however the function docs for in_edges say:
"For both directed and undirected graphs, the target of
an out-edge is required to be vertex v and the
source is required to be a vertex that is adjacent to v."
The latter implies that undirected graphs have to have two copies of each edge, one pointed each direction.
Which is correct? The former, I hope :-) Thanks.