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From: Wang Weiwei (wwwang_at_[hidden])
Date: 2006-07-15 09:07:55

>On Jul 14, 2006, at 10:54 AM, Wang Weiwei wrote:
>> Hello,
>> I have a graph type as follows:
>> namespace boost
>> {
>> enum vertex_flag_t { vertex_flag = 111 };
>> BOOST_INSTALL_PROPERTY(vertex, flag);
>> }
>> typedef boost::adjacency_list<boost::vecS, boost::vecS,
>> boost::undirectedS,
>> property<vertex_name_t, std::string,
>> property<vertex_flag_t, bool,
>> property<vertex_color_t, default_color_type> > >,
>> no_property> graph_t;
>> graph_t g;
>> That means I want to associate a string as name, a flag, and a
>> default color to each vertex of my graph,
>> now I want to add edges to my graph directly using the vertex'
>> properties instead of their descriptors,
>> e.g.
>> boost::add_edge("vertex1", "vertex2", g);
>> How can I accomplish this?
>You'll need to create a separate mapping from vertex names to vertex
> std::map<std::string, graph_t::vertex_descriptor> name_to_vertex;
> Doug

I've made the following template function to do the jod I want, as indicated by
its name - add vertices using their properties.

template<typename InputPropIterator, typename Graph,
                typename VertexPropMap> ////
AddVerticesByProp(InputPropIterator first, InputPropIterator last, Graph& g,
                                  VertexPropMap& pmap, ////
                                  typename std::map<
                                                  typename std::iterator_traits<InputPropIterator>::value_type,
                                                  typename boost::graph_traits<Graph>::vertex_descriptor
>& Prop2VertexMap)
        typedef boost::graph_traits<Graph>::vertex_descriptor vertex_t;
        typedef std::iterator_traits<InputPropIterator>::value_type prop_t;
        typedef std::map<prop_t, vertex_t> prop_vertex_map_t;

        for(; first != last; ++last)
                prop_vertex_map_t::iterator pos;
                bool inserted;
                vertex_t v;
                boost::tie(pos, inserted) = Prop2VertexMap.insert(std::make_pair(*first, vertex_t()));
                        v = add_vertex(g);
                        pmap[v] = *first;
                        pos->second = v;
                        v = pos->second;

I suppose it could more elegant if one can remove the template param 'VertexPropMap' and the
corresponding function param 'VertexPropMap& pmap', because the type 'VertexPropMap' is determined
and should be derived (I think) if the other 2 types are given.

To be clearer, the VertexPropMap is a map from 'typename std::iterator_traits<InputIterator>::value_type'
to 'typename boost::graph_traits<Graph>::vertex_descriptor'.

Similarly, as far as internal property map is concerned, the function param 'pmap' is also determined
and should be derived (I think) from 'g' and type info gien by the InputPropIterator.

What I need now is any help that can eliminate these 2 param's to make the funtion interface not so tedious.



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