Edit: /usr/include/boost/graph/sloan_ordering.hpp (15540B)
//
//=======================================================================
// Copyright 2002 Marc Wintermantel (wintermantel@even-ag.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)
//=======================================================================
//
#ifndef BOOST_GRAPH_SLOAN_HPP
#define BOOST_GRAPH_SLOAN_HPP
#define WEIGHT1 1 // default weight for the distance in the Sloan algorithm
#define WEIGHT2 2 // default weight for the degree in the Sloan algorithm
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
////////////////////////////////////////////////////////////
//
// Sloan-Algorithm for graph reordering
//(optimzes profile and wavefront, not primiraly bandwidth
//
////////////////////////////////////////////////////////////
namespace boost
{
/////////////////////////////////////////////////////////////////////////
// Function that returns the maximum depth of
// a rooted level strucutre (RLS)
//
/////////////////////////////////////////////////////////////////////////
template < class Distance > typename Distance::value_type RLS_depth(Distance& d)
{
typename Distance::value_type h_s = 0;
typename Distance::iterator iter;
for (iter = d.begin(); iter != d.end(); ++iter)
{
if (*iter > h_s)
{
h_s = *iter;
}
}
return h_s;
}
/////////////////////////////////////////////////////////////////////////
// Function that returns the width of the largest level of
// a rooted level strucutre (RLS)
//
/////////////////////////////////////////////////////////////////////////
template < class Distance, class my_int >
typename Distance::value_type RLS_max_width(Distance& d, my_int depth)
{
typedef typename Distance::value_type Degree;
// Searching for the maximum width of a level
std::vector< Degree > dummy_width(depth + 1, 0);
typename std::vector< Degree >::iterator my_it;
typename Distance::iterator iter;
Degree w_max = 0;
for (iter = d.begin(); iter != d.end(); ++iter)
{
dummy_width[*iter]++;
}
for (my_it = dummy_width.begin(); my_it != dummy_width.end(); ++my_it)
{
if (*my_it > w_max)
w_max = *my_it;
}
return w_max;
}
/////////////////////////////////////////////////////////////////////////
// Function for finding a good starting node for Sloan algorithm
//
// This is to find a good starting node. "good" is in the sense
// of the ordering generated.
/////////////////////////////////////////////////////////////////////////
template < class Graph, class ColorMap, class DegreeMap >
typename graph_traits< Graph >::vertex_descriptor sloan_start_end_vertices(
Graph& G, typename graph_traits< Graph >::vertex_descriptor& s,
ColorMap color, DegreeMap degree)
{
typedef typename property_traits< DegreeMap >::value_type Degree;
typedef typename graph_traits< Graph >::vertex_descriptor Vertex;
typedef typename std::vector<
typename graph_traits< Graph >::vertices_size_type >::iterator vec_iter;
typedef typename graph_traits< Graph >::vertices_size_type size_type;
typedef typename property_map< Graph, vertex_index_t >::const_type VertexID;
s = *(vertices(G).first);
Vertex e = s;
Vertex i;
Degree my_degree = get(degree, s);
Degree dummy, h_i, h_s, w_i, w_e;
bool new_start = true;
Degree maximum_degree = 0;
// Creating a std-vector for storing the distance from the start vertex in
// dist
std::vector< typename graph_traits< Graph >::vertices_size_type > dist(
num_vertices(G), 0);
// Wrap a property_map_iterator around the std::iterator
boost::iterator_property_map< vec_iter, VertexID, size_type, size_type& >
dist_pmap(dist.begin(), get(vertex_index, G));
// Creating a property_map for the indices of a vertex
typename property_map< Graph, vertex_index_t >::type index_map
= get(vertex_index, G);
// Creating a priority queue
typedef indirect_cmp< DegreeMap, std::greater< Degree > > Compare;
Compare comp(degree);
std::priority_queue< Vertex, std::vector< Vertex >, Compare > degree_queue(
comp);
// step 1
// Scan for the vertex with the smallest degree and the maximum degree
typename graph_traits< Graph >::vertex_iterator ui, ui_end;
for (boost::tie(ui, ui_end) = vertices(G); ui != ui_end; ++ui)
{
dummy = get(degree, *ui);
if (dummy < my_degree)
{
my_degree = dummy;
s = *ui;
}
if (dummy > maximum_degree)
{
maximum_degree = dummy;
}
}
// end 1
do
{
new_start = false; // Setting the loop repetition status to false
// step 2
// initialize the the disance std-vector with 0
for (typename std::vector< typename graph_traits<
Graph >::vertices_size_type >::iterator iter
= dist.begin();
iter != dist.end(); ++iter)
*iter = 0;
// generating the RLS (rooted level structure)
breadth_first_search(G, s,
visitor(
make_bfs_visitor(record_distances(dist_pmap, on_tree_edge()))));
// end 2
// step 3
// calculating the depth of the RLS
h_s = RLS_depth(dist);
// step 4
// pushing one node of each degree in an ascending manner into
// degree_queue
std::vector< bool > shrink_trace(maximum_degree, false);
for (boost::tie(ui, ui_end) = vertices(G); ui != ui_end; ++ui)
{
dummy = get(degree, *ui);
if ((dist[index_map[*ui]] == h_s) && (!shrink_trace[dummy]))
{
degree_queue.push(*ui);
shrink_trace[dummy] = true;
}
}
// end 3 & 4
// step 5
// Initializing w
w_e = (std::numeric_limits< Degree >::max)();
// end 5
// step 6
// Testing for termination
while (!degree_queue.empty())
{
i = degree_queue.top(); // getting the node with the lowest degree
// from the degree queue
degree_queue.pop(); // ereasing the node with the lowest degree from
// the degree queue
// generating a RLS
for (typename std::vector< typename graph_traits<
Graph >::vertices_size_type >::iterator iter
= dist.begin();
iter != dist.end(); ++iter)
*iter = 0;
breadth_first_search(G, i,
boost::visitor(make_bfs_visitor(
record_distances(dist_pmap, on_tree_edge()))));
// Calculating depth and width of the rooted level
h_i = RLS_depth(dist);
w_i = RLS_max_width(dist, h_i);
// Testing for termination
if ((h_i > h_s) && (w_i < w_e))
{
h_s = h_i;
s = i;
while (!degree_queue.empty())
degree_queue.pop();
new_start = true;
}
else if (w_i < w_e)
{
w_e = w_i;
e = i;
}
}
// end 6
} while (new_start);
return e;
}
//////////////////////////////////////////////////////////////////////////
// Sloan algorithm with a given starting Vertex.
//
// This algorithm requires user to provide a starting vertex to
// compute Sloan ordering.
//////////////////////////////////////////////////////////////////////////
template < class Graph, class OutputIterator, class ColorMap, class DegreeMap,
class PriorityMap, class Weight >
OutputIterator sloan_ordering(Graph& g,
typename graph_traits< Graph >::vertex_descriptor s,
typename graph_traits< Graph >::vertex_descriptor e,
OutputIterator permutation, ColorMap color, DegreeMap degree,
PriorityMap priority, Weight W1, Weight W2)
{
// typedef typename property_traits::value_type Degree;
typedef typename property_traits< PriorityMap >::value_type Degree;
typedef typename property_traits< ColorMap >::value_type ColorValue;
typedef color_traits< ColorValue > Color;
typedef typename graph_traits< Graph >::vertex_descriptor Vertex;
typedef typename std::vector<
typename graph_traits< Graph >::vertices_size_type >::iterator vec_iter;
typedef typename graph_traits< Graph >::vertices_size_type size_type;
typedef typename property_map< Graph, vertex_index_t >::const_type VertexID;
// Creating a std-vector for storing the distance from the end vertex in it
typename std::vector< typename graph_traits< Graph >::vertices_size_type >
dist(num_vertices(g), 0);
// Wrap a property_map_iterator around the std::iterator
boost::iterator_property_map< vec_iter, VertexID, size_type, size_type& >
dist_pmap(dist.begin(), get(vertex_index, g));
breadth_first_search(g, e,
visitor(make_bfs_visitor(record_distances(dist_pmap, on_tree_edge()))));
// Creating a property_map for the indices of a vertex
typename property_map< Graph, vertex_index_t >::type index_map
= get(vertex_index, g);
// Sets the color and priority to their initial status
Degree cdeg;
typename graph_traits< Graph >::vertex_iterator ui, ui_end;
for (boost::tie(ui, ui_end) = vertices(g); ui != ui_end; ++ui)
{
put(color, *ui, Color::white());
cdeg = get(degree, *ui) + 1;
put(priority, *ui, W1 * dist[index_map[*ui]] - W2 * cdeg);
}
// Priority list
typedef indirect_cmp< PriorityMap, std::greater< Degree > > Compare;
Compare comp(priority);
std::list< Vertex > priority_list;
// Some more declarations
typename graph_traits< Graph >::out_edge_iterator ei, ei_end, ei2, ei2_end;
Vertex u, v, w;
put(color, s,
Color::green()); // Sets the color of the starting vertex to gray
priority_list.push_front(s); // Puts s into the priority_list
while (!priority_list.empty())
{
priority_list.sort(comp); // Orders the elements in the priority list in
// an ascending manner
u = priority_list
.front(); // Accesses the last element in the priority list
priority_list
.pop_front(); // Removes the last element in the priority list
if (get(color, u) == Color::green())
{
// for-loop over all out-edges of vertex u
for (boost::tie(ei, ei_end) = out_edges(u, g); ei != ei_end; ++ei)
{
v = target(*ei, g);
put(priority, v, get(priority, v) + W2); // updates the priority
if (get(color, v)
== Color::white()) // test if the vertex is inactive
{
put(color, v,
Color::green()); // giving the vertex a preactive status
priority_list.push_front(
v); // writing the vertex in the priority_queue
}
}
}
// Here starts step 8
*permutation++
= u; // Puts u to the first position in the permutation-vector
put(color, u, Color::black()); // Gives u an inactive status
// for loop over all the adjacent vertices of u
for (boost::tie(ei, ei_end) = out_edges(u, g); ei != ei_end; ++ei)
{
v = target(*ei, g);
if (get(color, v) == Color::green())
{ // tests if the vertex is inactive
put(color, v,
Color::red()); // giving the vertex an active status
put(priority, v, get(priority, v) + W2); // updates the priority
// for loop over alll adjacent vertices of v
for (boost::tie(ei2, ei2_end) = out_edges(v, g); ei2 != ei2_end;
++ei2)
{
w = target(*ei2, g);
if (get(color, w) != Color::black())
{ // tests if vertex is postactive
put(priority, w,
get(priority, w) + W2); // updates the priority
if (get(color, w) == Color::white())
{
put(color, w, Color::green()); // gives the vertex a
// preactive status
priority_list.push_front(
w); // puts the vertex into the priority queue
} // end if
} // end if
} // end for
} // end if
} // end for
} // end while
return permutation;
}
/////////////////////////////////////////////////////////////////////////////////////////
// Same algorithm as before, but without the weights given (taking default
// weights
template < class Graph, class OutputIterator, class ColorMap, class DegreeMap,
class PriorityMap >
OutputIterator sloan_ordering(Graph& g,
typename graph_traits< Graph >::vertex_descriptor s,
typename graph_traits< Graph >::vertex_descriptor e,
OutputIterator permutation, ColorMap color, DegreeMap degree,
PriorityMap priority)
{
return sloan_ordering(
g, s, e, permutation, color, degree, priority, WEIGHT1, WEIGHT2);
}
//////////////////////////////////////////////////////////////////////////
// Sloan algorithm without a given starting Vertex.
//
// This algorithm finds a good starting vertex itself to
// compute Sloan-ordering.
//////////////////////////////////////////////////////////////////////////
template < class Graph, class OutputIterator, class Color, class Degree,
class Priority, class Weight >
inline OutputIterator sloan_ordering(Graph& G, OutputIterator permutation,
Color color, Degree degree, Priority priority, Weight W1, Weight W2)
{
typedef typename boost::graph_traits< Graph >::vertex_descriptor Vertex;
Vertex s, e;
e = sloan_start_end_vertices(G, s, color, degree);
return sloan_ordering(
G, s, e, permutation, color, degree, priority, W1, W2);
}
/////////////////////////////////////////////////////////////////////////////////////////
// Same as before, but without given weights (default weights are taken instead)
template < class Graph, class OutputIterator, class Color, class Degree,
class Priority >
inline OutputIterator sloan_ordering(Graph& G, OutputIterator permutation,
Color color, Degree degree, Priority priority)
{
return sloan_ordering(
G, permutation, color, degree, priority, WEIGHT1, WEIGHT2);
}
} // namespace boost
#endif // BOOST_GRAPH_SLOAN_HPP