1 // Copyright 2004 The Trustees of Indiana University.
2
3 // Use, modification and distribution is subject to the Boost Software
4 // License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
5 // http://www.boost.org/LICENSE_1_0.txt)
6
7 // Authors: Douglas Gregor
8 // Andrew Lumsdaine
9
10 #include <boost/graph/use_mpi.hpp>
11 #include <boost/throw_exception.hpp>
12 #include <boost/serialization/vector.hpp>
13 #include <boost/graph/distributed/page_rank.hpp>
14 #include <boost/test/minimal.hpp>
15 #include <boost/graph/distributed/adjacency_list.hpp>
16 #include <boost/graph/distributed/mpi_process_group.hpp>
17 #include <boost/test/minimal.hpp>
18 #include <vector>
19 #include <iostream>
20 #include <stdlib.h>
21
22 #ifdef BOOST_NO_EXCEPTIONS
23 void
throw_exception(std::exception const & ex)24 boost::throw_exception(std::exception const& ex)
25 {
26 std::cout << ex.what() << std::endl;
27 abort();
28 }
29 #endif
30
31 using namespace boost;
32 using boost::graph::distributed::mpi_process_group;
33
close_to(double x,double y)34 bool close_to(double x, double y)
35 {
36 double diff = x - y;
37 if (diff < 0) diff = -diff;
38 double base = (y == 0? x : y);
39 if (base != 0) return diff / base < 0.01;
40 else return true;
41 }
42
43 // Make convenient labels for the vertices
44 enum vertex_id_t { A, B, C, D, N };
45
test_distributed_page_rank(int iterations)46 void test_distributed_page_rank(int iterations)
47 {
48 using namespace boost::graph;
49
50 // create a typedef for the Graph type
51 typedef adjacency_list<vecS,
52 distributedS<mpi_process_group, vecS>,
53 bidirectionalS
54 > Graph;
55 typedef graph_traits<Graph>::vertex_descriptor vertex_descriptor;
56
57 // writing out the edges in the graph
58 typedef std::pair<int, int> Edge;
59 Edge edge_array[] =
60 { Edge(A,B), Edge(A,C), Edge(B,C), Edge(C,A), Edge(D,C) };
61 const int num_edges = sizeof(edge_array)/sizeof(edge_array[0]);
62
63 // declare a graph object
64 Graph g(edge_array, edge_array + num_edges, N);
65
66 std::vector<double> ranks(num_vertices(g));
67
68 page_rank(g,
69 make_iterator_property_map(ranks.begin(),
70 get(boost::vertex_index, g)),
71 n_iterations(iterations), 0.85, N);
72
73 double local_sum = 0.0;
74 for(unsigned int i = 0; i < num_vertices(g); ++i) {
75 std::cout << (char)('A' + g.distribution().global(i)) << " = "
76 << ranks[i] << std::endl;
77 local_sum += ranks[i];
78 }
79 double sum=0.;
80 boost::mpi::reduce(communicator(g.process_group()),
81 local_sum, sum, std::plus<double>(), 0);
82 if (process_id(g.process_group()) == 0) {
83 std::cout << "Sum = " << sum << "\n\n";
84 BOOST_CHECK(close_to(sum, 4)); // 1 when alpha=0
85 }
86
87 // double expected_ranks0[N] = {0.400009, 0.199993, 0.399998, 0.0};
88 double expected_ranks[N] = {1.49011, 0.783296, 1.5766, 0.15};
89 for (int i = 0; i < N; ++i) {
90 vertex_descriptor v = vertex(i, g);
91 if (v != Graph::null_vertex()
92 && owner(v) == process_id(g.process_group())) {
93 BOOST_CHECK(close_to(ranks[local(v)], expected_ranks[i]));
94 }
95 }
96 }
97
test_main(int argc,char * argv[])98 int test_main(int argc, char* argv[])
99 {
100 mpi::environment env(argc, argv);
101
102 int iterations = 50;
103 if (argc > 1) {
104 iterations = atoi(argv[1]);
105 }
106
107 test_distributed_page_rank(iterations);
108
109 return 0;
110 }
111