Re: [Boost-users] Boost Graph: edge indices

Subject: Re: [Boost-users] Boost Graph: edge indices
From: Jeremiah Willcock (jewillco_at_[hidden])
Date: 2010-04-01 17:18:06

On Thu, 1 Apr 2010, Trevor Harmon wrote:

> On Apr 1, 2010, at 6:40 AM, Jeremiah Willcock wrote:
>
>> Note that you need to fill in the edge indices
>
>
> Okay, so whenever I add an edge I need to assign it a unique index myself. 
> Here's how I'm doing it for the initial construction of the graph:
>
> size_t edgeIndex = 0;
> for (...) {
>  Vertex u = ...
>  Vertex v = ...
>  Edge edge;
>  bool inserted;
>  tie(edge, inserted) = add_edge(u, v, g);
>  EdgeIndexMap edgeIndexMap = get(edge_index, g);
>  put(edgeIndexMap, edge, edgeIndex++);
> }
>
> Does that look right? It seems to work, but I'm wondering if it's the best 
> way.

That's fine, but you don't need to fetch edgeIndexMap every time -- you 
can get it outside the loop then use it repeatedly.  You can also create 
the edges without filling in the edge indices then do a loop over edges(g) 
to fill them all in at once.

-- Jeremiah Willcock