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boostboost-graph

How to create a PropertyMap for a boost graph using listS as vertex container?


I have a boost graph defined as

typedef boost::adjacency_list<boost::setS, boost::listS,
        boost::undirectedS, CoordNode, CoordSegment> BGraph;
typedef boost::graph_traits<BGraph>::vertex_descriptor  VertexDesc;
BGraph _graph;

and I want to know the connected components of same graph with

 int num = boost::connected_components(_graph, propMap);

I already tried to create the required writable property map (propMap) with

typedef  std::map<VertexDesc, size_t> IndexMap;
IndexMap mapIndex;
boost::associative_property_map<IndexMap> propMap(mapIndex);
VertexIterator di, dj;
boost::tie(di, dj) = boost::vertices(_graph);
for(di; di != dj; ++di){
    boost::put(propMap, (*di), 0);
}

but that doesn't work; I get compilations errors.

If the vertex container would be vecS, it would be easier, because a simple array or vector would suffice. But what am I supposed to pass to this function if I have listS as the vertex container?

How can I create the necessary writable property map? Can somebody give me an example?


Solution

  • Works!

    typedef boost::adjacency_list
        <boost::setS, boost::listS,
            boost::undirectedS, 
            boost::no_property,
            boost::no_property> Graph;
        typedef boost::graph_traits<Graph>::vertex_iterator VertexIterator;
        typedef boost::graph_traits<Graph>::vertex_descriptor   VertexDesc;
        typedef std::map<VertexDesc, size_t> VertexDescMap; 
    
    Graph graph;
    
    ...
    
    
    VertexDescMap idxMap;
    boost::associative_property_map<VertexDescMap> indexMap(idxMap);
    VertexIterator di, dj;
    boost::tie(di, dj) = boost::vertices(_graph);
    for(int i = 0; di != dj; ++di,++i){
        boost::put(indexMap, (*di), i);
    }
    
    
    std::map<VertexDesc, size_t> compMap;
    boost::associative_property_map<VertexDescMap> componentMap(compMap);            
    boost::associative_property_map<VertexDescMap>& componentMap;
    
    boost::connected_components(_graph, componentMap, boost::vertex_index_map(indexMap));