[Boost-users] [BGL] Issue using connected_components

Subject: [Boost-users] [BGL] Issue using connected_components
From: Nicolas Saunier (nicolas.saunier_at_[hidden])
Date: 2011-12-07 12:21:34

Hi,

here is a simplified code sample that I cannot get to work. I use 
bundled properties for an undirected graph and I do not find what should 
be the type of the component map (or property map) that should be passed 
as the second argument of the connected_components function. The sample 
is useless since only integers are for vertices.

#include <boost/graph/adjacency_list.hpp>
#include <boost/shared_ptr.hpp>
#include <boost/graph/connected_components.hpp>

using namespace boost;
using namespace std;

struct FeatureTrajectory {
   int id;
};

struct FeatureConnection {
   float minDistance;
   float maxDistance;
};

struct VertexInformation {
   shared_ptr<FeatureTrajectory> feature;
};

typedef adjacency_list < listS, listS, undirectedS, VertexInformation, 
FeatureConnection> FeatureGraph;

int main() {
   FeatureGraph g;
   FeatureGraph::vertex_descriptor u, v;
   FeatureGraph::edge_descriptor e;

   u = add_vertex(g);
   v = add_vertex(g);
   bool unused;
   tie(e, unused) = add_edge(u, v, g);

   g[e].minDistance = 0.;
   g[e].maxDistance = 1.;

   g[u].feature = shared_ptr<FeatureTrajectory>(new FeatureTrajectory());
   g[u].feature->id =11;
   g[v].feature = shared_ptr<FeatureTrajectory>(new FeatureTrajectory());
   g[v].feature->id =12;

   cout << num_vertices(g) << " " << num_edges(g) << endl;

   vector_property_map< graph_traits<FeatureGraph>::vertices_size_type > 
components(num_vertices(g));

   int num = connected_components(g, &components[0]);

   return 0;
}

The final error is:

/usr/include/boost/graph/connected_components.hpp:46: error: no matching 
function for call to ‘put(long unsigned int*&, void*&, long unsigned int&)’

Can someone help me get it to work and to understand property maps?

Thanks!

Nicolas
-- 
Nicolas Saunier, ing. jr, Ph.D.
Professeur Adjoint / Assistant Professor
Département des génies civil, géologique et des mines (CGM)
École Polytechnique de Montréal
http://nicolas.saunier.confins.net