boost-property-map

Can someone explain to a Boost beginner like me what is a property map is in Boost? I came across this when trying to use the BGL for calculating strong connected components. I went throw the documentation for the property map and graph module and still don't know what to make of it. Take this code, for example: - what is the make_iterator_property_map function doing? - and what is the meaning of this code: get(vertex_index, G) ? #include <boost/config.hpp> #include <vector> #include <iostream> #include <boost/graph/strong_components.hpp> #include <boost/graph/adjacency_list.hpp> int main() {

I am learning the Fruchterman-Reingold algorithm in Boost Graph Library. By reading the document, I know that the algorithm is to compute the positions for all nodes in terms of graph layout, but my problem is I cannot understand the calculation steps of attractive forces in Boost Graph Library. For example, if the topology is rectangle with height 100 and width 100, each vertex is labelled as string, and the relation between each pair vertex as: "0" "5" "Kevin" "Martin" "Ryan" "Leo" "Y" "S" "Kevin" "S" "American" "USA" Each row denotes the two labelled vertices are connected. The formula of

How would I create a graph, such that the property map (weight of edges) is different in each property map? Is it possible to create such a property map? Like an array of property maps? I have not seen anyone on the Internet using it, could I have an example? Graph g(10); // graph with 10 nodes cin>>a>>b>>weight1>>weight2>>weight3>>weight4; and put each weight in a property map. You can compose a property map in various ways. The simplest approach would seem something like: Using C++11 lambdas with function_property_map Live On Coliru #include <boost/property_map/function_property_map.hpp>

I'm using Boost Graph Libraries and need to use a weightmap which is not constant, but which is a function of a parameter K (i.e. the edge costs depend on K). In practice, given the following code: #include <boost/config.hpp> #include <iostream> #include <fstream> #include <boost/graph/graph_traits.hpp> #include <boost/graph/dijkstra_shortest_paths.hpp> #include <boost/graph/adjacency_list.hpp> struct Edge { Edge(float weight_) : weight(weight_) {} float weight; float getWeight(int K) { return K*weight; } }; int main(int, char**){ typedef boost::adjacency_list < boost::vecS, boost::vecS, boost

I have a boost graph with multiples weights for each edges (imagine one set of weights per hour of the day). Every one of those weights values is stored in a propretyEdge class : class propretyEdge { std::map<std::string,double> weights; // Date indexed } I created a graph with those properties, and then filled it with the right values. The problem is now that I want to launch the Dijkstra algorithm over a particular set of weight on the graph : for example a function that could be : void Dijkstra (string date, parameters ... ) That would use the weights[date] value for each Edge of the graph.