Re: [igraph] calculating the number of edges on the boundary of S

[Tamas Nepusz]

> after the steps you explain to me ,I use the graph.strength()  to get the
> number of edges pointed out for each community, But I was wondering is it
> any way to assign  the id of each vertex  in the contracted graph exactly
> the membership number of the community in the original graph.
This is exactly what happens if you use contract.vertices() with the membership
vector. contract.vertices() expects a vector that tells the "new" ID of each
vertex after the contraction. So, if the value belonging to a certain vertex in
the membership vector is X, then the vertex will be merged into the "new" node
with ID=X in the contracted graph.

Best,
T.