1 // (C) Copyright Andrew Sutton 2007
2 //
3 // Use, modification and distribution are subject to the
4 // Boost Software License, Version 1.0 (See accompanying file
5 // LICENSE_1_0.txt or http://www.boost.org/LICENSE_1_0.txt)
6
7 //[closeness_centrality_example
8 #include <iostream>
9 #include <iomanip>
10
11 #include <boost/graph/undirected_graph.hpp>
12 #include <boost/graph/exterior_property.hpp>
13 #include <boost/graph/floyd_warshall_shortest.hpp>
14 #include <boost/graph/closeness_centrality.hpp>
15 #include <boost/graph/property_maps/constant_property_map.hpp>
16 #include "helper.hpp"
17
18 using namespace std;
19 using namespace boost;
20
21 // The Actor type stores the name of each vertex in the graph.
22 struct Actor
23 {
24 string name;
25 };
26
27 // Declare the graph type and its vertex and edge types.
28 typedef undirected_graph< Actor > Graph;
29 typedef graph_traits< Graph >::vertex_descriptor Vertex;
30 typedef graph_traits< Graph >::edge_descriptor Edge;
31
32 // The name map provides an abstract accessor for the names of
33 // each vertex. This is used during graph creation.
34 typedef property_map< Graph, string Actor::* >::type NameMap;
35
36 // Declare a matrix type and its corresponding property map that
37 // will contain the distances between each pair of vertices.
38 typedef exterior_vertex_property< Graph, int > DistanceProperty;
39 typedef DistanceProperty::matrix_type DistanceMatrix;
40 typedef DistanceProperty::matrix_map_type DistanceMatrixMap;
41
42 // Declare the weight map so that each edge returns the same value.
43 typedef constant_property_map< Edge, int > WeightMap;
44
45 // Declare a container and its corresponding property map that
46 // will contain the resulting closeness centralities of each
47 // vertex in the graph.
48 typedef boost::exterior_vertex_property< Graph, float > ClosenessProperty;
49 typedef ClosenessProperty::container_type ClosenessContainer;
50 typedef ClosenessProperty::map_type ClosenessMap;
51
main(int argc,char * argv[])52 int main(int argc, char* argv[])
53 {
54 // Create the graph and a property map that provides access to[
55 // tha actor names.
56 Graph g;
57 NameMap nm(get(&Actor::name, g));
58
59 // Read the graph from standard input.
60 read_graph(g, nm, cin);
61
62 // Compute the distances between all pairs of vertices using
63 // the Floyd-Warshall algorithm. Note that the weight map is
64 // created so that every edge has a weight of 1.
65 DistanceMatrix distances(num_vertices(g));
66 DistanceMatrixMap dm(distances, g);
67 WeightMap wm(1);
68 floyd_warshall_all_pairs_shortest_paths(g, dm, weight_map(wm));
69
70 // Compute the closeness centrality for graph.
71 ClosenessContainer cents(num_vertices(g));
72 ClosenessMap cm(cents, g);
73 all_closeness_centralities(g, dm, cm);
74
75 // Print the closeness centrality of each vertex.
76 graph_traits< Graph >::vertex_iterator i, end;
77 for (boost::tie(i, end) = vertices(g); i != end; ++i)
78 {
79 cout << setw(12) << setiosflags(ios::left) << g[*i].name << get(cm, *i)
80 << endl;
81 }
82
83 return 0;
84 }
85 //]
86