[Boost-users] Bidirectional Graph and undirected graphs

Subject: [Boost-users] Bidirectional Graph and undirected graphs
From: Daniel Russel (drussel_at_[hidden])
Date: 2009-05-13 14:39:24

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.