Hi Monks, there are a number of perl modules for dealing with graph data structures. I'm trying to calculate 'betweeness centrality' for a particular node P where this is the number of times shortest paths between pairs of nodes on a graph pass through node P.

I've tried to do this by calculating shortest paths between each pair of nodes but have the problem that implementations of shortest path algorithms will only return one path where there are multiple shortest paths of the same length. I need all shortest paths. For example, there a 2 paths of length 3 between nodes 1 and 4 in the following example. This bit of code will only return one of them 

#!/usr/bin/perl

use Boost::Graph;
my $graph = new Boost::Graph(directed=>0, net_name=>'Graph Name', net_
+id=>1000); 

# add edges
$graph->add_edge(node1=>'1', node2=>'2', weight=>1);
$graph->add_edge(node1=>'1', node2=>'3', weight=>1);
$graph->add_edge(node1=>'2', node2=>'4', weight=>1);
$graph->add_edge(node1=>'3', node2=>'4', weight=>1);
my $path=$graph->dijkstra_shortest_path('1','4');

print @{$path->{'path'}};

[download]
Anybody have any ideas?
cheers
ps
Algorithm::SocialNetwork won't install so this is out.

In reply to Graph modules by nosbod

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