I have to  build a graph from  data in a file, some information is strings which are related to vertexes. I want to prove if those vertexes already exist in the graph before the insert operation. Next is the source:

 

typedef adjacency_matrix<undirectedS,VertexProperty,EdgeProperty> UGraph;  // an undirected graph

 UGraph g(0);   // start from scratch

property_map<UGraph, edge_name_t>::type ename = get(edge_name, g); // not sure if this is right (the graph have no elements at this point)
property_map<UGraph, vertex_name_t>::type vname = get(vertex_name, g);
typedef property_map<UGraph, vertex_name_t>::type vname_type;

typedef boost::property_traits<vname_type>::key_type vktype;
typedef boost::property_traits<vname_type>::value_type vvtype;

 

vktype indice_nombre;
vvtype valor_nombre;

 

for(i=0;i<datgen.NumHilos;i++){ 
 valor_nombre = hiloNormal[i].viaOrigen; /// here we get the string

 indice_nombre = vname[valor_nombre]; /// here I try to get the index

/// I think this is not posible because there isn't [] operator in this way
 valor_nombre = vname[1]; /// if I do this the compiler is right but that isn't useful for me because the information I have is the string not the index.I can use vertex iterators and search for the string, but if posible i prefer not to do that.

 

thanks a lot.