Get specific edge with boost::graph

Question

I'm using boost::graph and I have two vertex_descriptors. What is the quickest way to get the edge between them, without iterating over all the edges?

score 58 · Accepted Answer · answered Jan 19 '11 at 12:11

58

Ok, I found it out. boost::edge(u,v,g) returns pair<edge_descriptor, bool> where the bool is whether the edge exists. So in my case I know it does, so I use the expression:

boost::edge(u,v,g).first

answered Jan 19 '11 at 12:11

Amir Rachum

76,817
74
166
248

2

Actually, it should be `boost::edge(u,v,g).second`, if you want the `bool` value... – tnull Feb 17 '15 at 11:16
3

@tnull since I know the edge exists and I'm looking for the edge itself, `first` is the attribute I need. – Amir Rachum Apr 08 '15 at 17:15

score 7 · Answer 2 · answered Jan 21 '11 at 05:34

7

There is also a function boost::lookup_edge() in boost/graph/lookup_edge.hpp; that function dispatches to either edge() or out_edges() and a search based on the particular graph type you are using.

answered Jan 21 '11 at 05:34

Jeremiah Willcock

30,161
7
76
78

Get specific edge with boost::graph

2 Answers2