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libs/graph/example/sloan_ordering.cpp

//
//=======================================================================
// Copyright 2002 Marc Wintermantel (wintermantel@imes.mavt.ethz.ch)
// ETH Zurich, Center of Structure Technologies
// (https://web.archive.org/web/20050307090307/http://www.structures.ethz.ch/)
//
// Distributed under the Boost Software License, Version 1.0.
// (See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
//=======================================================================
//

#include <boost/config.hpp>
#include <vector>
#include <iostream>
#include <boost/graph/adjacency_list.hpp>
#include <boost/graph/sloan_ordering.hpp>
#include <boost/graph/properties.hpp>
#include <boost/graph/bandwidth.hpp>
#include <boost/graph/profile.hpp>
#include <boost/graph/wavefront.hpp>

using std::cout;
using std::endl;

/*
  Sample Output
  #####################################
  ### First light of sloan-ordering ###
  #####################################

  original bandwidth: 8
  original profile: 42
  original max_wavefront: 7
  original aver_wavefront: 4.2
  original rms_wavefront: 4.58258

  Starting vertex: 0
  Pseudoperipheral vertex: 9
  Pseudoperipheral radius: 4

  Sloan ordering starting at: 0
    0 8 3 7 5 2 4 6 1 9
    bandwidth: 4
    profile: 28
    max_wavefront: 4
    aver_wavefront: 2.8
    rms_wavefront: 2.93258

  Sloan ordering without a start-vertex:
    8 0 3 7 5 2 4 6 1 9
    bandwidth: 4
    profile: 27
    max_wavefront: 4
    aver_wavefront: 2.7
    rms_wavefront: 2.84605

  ###############################
  ### sloan-ordering finished ###
  ###############################
*/

int main(int, char*[])
{
    cout << endl;
    cout << "#####################################" << endl;
    cout << "### First light of sloan-ordering ###" << endl;
    cout << "#####################################" << endl << endl;

    using namespace boost;
    using namespace std;

    // Defining the graph type
    typedef adjacency_list< setS, vecS, undirectedS,
        property< vertex_color_t, default_color_type,
            property< vertex_degree_t, int,
                property< vertex_priority_t, double > > > >
        Graph;

    typedef graph_traits< Graph >::vertex_descriptor Vertex;
    typedef graph_traits< Graph >::vertices_size_type size_type;

    typedef std::pair< std::size_t, std::size_t > Pair;

    Pair edges[14] = { Pair(0, 3), // a-d
        Pair(0, 5), // a-f
        Pair(1, 2), // b-c
        Pair(1, 4), // b-e
        Pair(1, 6), // b-g
        Pair(1, 9), // b-j
        Pair(2, 3), // c-d
        Pair(2, 4), // c-e
        Pair(3, 5), // d-f
        Pair(3, 8), // d-i
        Pair(4, 6), // e-g
        Pair(5, 6), // f-g
        Pair(5, 7), // f-h
        Pair(6, 7) }; // g-h

    // Creating a graph and adding the edges from above into it
    Graph G(10);
    for (int i = 0; i < 14; ++i)
        add_edge(edges[i].first, edges[i].second, G);

    // Creating two iterators over the vertices
    graph_traits< Graph >::vertex_iterator ui, ui_end;

    // Creating a property_map with the degrees of the degrees of each vertex
    property_map< Graph, vertex_degree_t >::type deg = get(vertex_degree, G);
    for (boost::tie(ui, ui_end) = vertices(G); ui != ui_end; ++ui)
        deg[*ui] = degree(*ui, G);

    // Creating a property_map for the indices of a vertex
    property_map< Graph, vertex_index_t >::type index_map
        = get(vertex_index, G);

    std::cout << "original bandwidth: " << bandwidth(G) << std::endl;
    std::cout << "original profile: " << profile(G) << std::endl;
    std::cout << "original max_wavefront: " << max_wavefront(G) << std::endl;
    std::cout << "original aver_wavefront: " << aver_wavefront(G) << std::endl;
    std::cout << "original rms_wavefront: " << rms_wavefront(G) << std::endl;

    // Creating a vector of vertices
    std::vector< Vertex > sloan_order(num_vertices(G));
    // Creating a vector of size_type
    std::vector< size_type > perm(num_vertices(G));

    {

        // Setting the start node
        Vertex s = vertex(0, G);
        int ecc; // defining a variable for the pseudoperipheral radius

        // Calculating the pseudoeperipheral node and radius
        Vertex e = pseudo_peripheral_pair(
            G, s, ecc, get(vertex_color, G), get(vertex_degree, G));

        cout << endl;
        cout << "Starting vertex: " << s << endl;
        cout << "Pseudoperipheral vertex: " << e << endl;
        cout << "Pseudoperipheral radius: " << ecc << endl << endl;

        // Sloan ordering
        sloan_ordering(G, s, e, sloan_order.begin(), get(vertex_color, G),
            get(vertex_degree, G), get(vertex_priority, G));

        cout << "Sloan ordering starting at: " << s << endl;
        cout << "  ";

        for (std::vector< Vertex >::const_iterator i = sloan_order.begin();
             i != sloan_order.end(); ++i)
            cout << index_map[*i] << " ";
        cout << endl;

        for (size_type c = 0; c != sloan_order.size(); ++c)
            perm[index_map[sloan_order[c]]] = c;
        std::cout << "  bandwidth: "
                  << bandwidth(G,
                         make_iterator_property_map(
                             &perm[0], index_map, perm[0]))
                  << std::endl;
        std::cout << "  profile: "
                  << profile(G,
                         make_iterator_property_map(
                             &perm[0], index_map, perm[0]))
                  << std::endl;
        std::cout << "  max_wavefront: "
                  << max_wavefront(G,
                         make_iterator_property_map(
                             &perm[0], index_map, perm[0]))
                  << std::endl;
        std::cout << "  aver_wavefront: "
                  << aver_wavefront(G,
                         make_iterator_property_map(
                             &perm[0], index_map, perm[0]))
                  << std::endl;
        std::cout << "  rms_wavefront: "
                  << rms_wavefront(G,
                         make_iterator_property_map(
                             &perm[0], index_map, perm[0]))
                  << std::endl;
    }

    /////////////////////////////////////////////////
    // Version including finding a good starting point
    /////////////////////////////////////////////////

    {
        // sloan_ordering
        sloan_ordering(G, sloan_order.begin(), get(vertex_color, G),
            make_degree_map(G), get(vertex_priority, G));

        cout << endl << "Sloan ordering without a start-vertex:" << endl;
        cout << "  ";
        for (std::vector< Vertex >::const_iterator i = sloan_order.begin();
             i != sloan_order.end(); ++i)
            cout << index_map[*i] << " ";
        cout << endl;

        for (size_type c = 0; c != sloan_order.size(); ++c)
            perm[index_map[sloan_order[c]]] = c;
        std::cout << "  bandwidth: "
                  << bandwidth(G,
                         make_iterator_property_map(
                             &perm[0], index_map, perm[0]))
                  << std::endl;
        std::cout << "  profile: "
                  << profile(G,
                         make_iterator_property_map(
                             &perm[0], index_map, perm[0]))
                  << std::endl;
        std::cout << "  max_wavefront: "
                  << max_wavefront(G,
                         make_iterator_property_map(
                             &perm[0], index_map, perm[0]))
                  << std::endl;
        std::cout << "  aver_wavefront: "
                  << aver_wavefront(G,
                         make_iterator_property_map(
                             &perm[0], index_map, perm[0]))
                  << std::endl;
        std::cout << "  rms_wavefront: "
                  << rms_wavefront(G,
                         make_iterator_property_map(
                             &perm[0], index_map, perm[0]))
                  << std::endl;
    }

    cout << endl;
    cout << "###############################" << endl;
    cout << "### sloan-ordering finished ###" << endl;
    cout << "###############################" << endl << endl;
    return 0;
}