Re: [Boost-users] BGL - accessing component subgraphs.

Subject: Re: [Boost-users] BGL - accessing component subgraphs.
From: Adam Spargo (aws_at_[hidden])
Date: 2010-07-15 12:09:17

> There is a subgraph class in BGL, and also filtered_graph.  Are the subgraphs 
> you're working with induced subgraphs (i.e., you do not selectively remove 
> edges other than by filtering out their endpoints)? The subgraph class seems 
> to make the subgraphs look more like normal graphs, while filtered_graph is 
> probably much simpler (it doesn't update num_vertices() to match the subgraph 
> size, for example).  If you're passing in something like the connected 
> components of a graph individually, that is an induced subgraph and so either 
> of those classes will work directly.

Thanks, I think that it is filtered_graph that I want as the vertex 
indices are meaningful to me. I've adapted the filtered_graph example to 
do what I want on a small graph, code attached. Just a couple questions - 
is finding the components, then copying into a property map the most 
efficient method, could I have the component algorithm populate the 
property map directly. Second, I could only get this working by adding an 
edge filter AND a vertex filter, but really I only need a vertex filter, 
how to pass an 'empty' function object to the constructor?

Thanks for your help,

Adam.

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