Thank you very much; I had a hunch it had something to do w/default parameters but was unsure how the library handled them. I appreciate the help, Emily Message: 3 Date: Tue, 29 Sep 2009 17:07:30 -0400 (EDT) From: Jeremiah Willcock <jewillco@osl.iu.edu> To: boost-users@lists.boost.org Subject: Re: [Boost-users] request for help re: brandes_betweenness_centrality for weighted graph Message-ID: <alpine.OSX.1.10.0909291705020.77663@marvin.osl.iu.edu> Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed On Tue, 29 Sep 2009, allenem@pcbi.upenn.edu wrote:

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Hi-

I've just recently started to use the BGL and was wondering if someone could provide an example (and/or just let me know where I am going wrong) in trying to execute the brandes_betweenness_centrality algorithm for a weighted graph. Below are the relevant code snippets from my program. I am able to compile and run the code, and have successfully iterated over all elements (vertices, edges, and "interaction_weights" to verify that the data are stored correctly) but the calculated betweenness values are the same whether or not I use the edge weight map, which suggests that they are not being considered in the calculation even when passed as a parameter to the brandes_betweenness_centrality function. What am I missing?

The three-parameter version of brandes_betweenness_centrality has its third parameter as the (output) edge centrality map, not the weight map which you are trying to provide. Try using the named parameter version (as shown on <URL:http://www.boost.org/doc/libs/1_40_0/libs/graph/doc/betweenness_centrality.html>). How to provide named parameters is described at <URL:http://www.boost.org/doc/libs/1_40_0/libs/graph/doc/bgl_named_params.html>. -- Jeremiah Willcock