diff -r 666f914201fb -r 2fe1408b6811 epoc32/include/stdapis/boost/graph/king_ordering.hpp --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/epoc32/include/stdapis/boost/graph/king_ordering.hpp Tue Mar 16 16:12:26 2010 +0000 @@ -0,0 +1,320 @@ +//======================================================================= +// Copyright 1997, 1998, 1999, 2000 University of Notre Dame. +// Copyright 2004, 2005 Trustees of Indiana University +// Authors: Andrew Lumsdaine, Lie-Quan Lee, Jeremy G. Siek, +// Doug Gregor, D. Kevin McGrath +// +// 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_KING_HPP +#define BOOST_GRAPH_KING_HPP + +#include +#include + +/* + King Algorithm for matrix reordering +*/ + +namespace boost { + namespace detail { + template + class bfs_king_visitor:public default_bfs_visitor + { + public: + bfs_king_visitor(OutputIterator *iter, Buffer *b, Compare compare, + PseudoDegreeMap deg, std::vector loc, VecMap color, + VertexIndexMap vertices): + permutation(iter), Qptr(b), degree(deg), comp(compare), + Qlocation(loc), colors(color), vertex_map(vertices) { } + + template + void finish_vertex(Vertex, Graph& g) { + typename graph_traits::out_edge_iterator ei, ei_end; + Vertex v, w; + + typedef typename std::deque::iterator iterator; + typedef typename std::deque::reverse_iterator reverse_iterator; + + reverse_iterator rend = Qptr->rend()-index_begin; + reverse_iterator rbegin = Qptr->rbegin(); + + + //heap the vertices already there + std::make_heap(rbegin, rend, boost::bind(comp, _2, _1)); + + unsigned i = 0; + + for(i = index_begin; i != Qptr->size(); ++i){ + colors[get(vertex_map, (*Qptr)[i])] = 1; + Qlocation[get(vertex_map, (*Qptr)[i])] = i; + } + + i = 0; + + for( ; rbegin != rend; rend--){ + percolate_down(i); + w = (*Qptr)[index_begin+i]; + for (tie(ei, ei_end) = out_edges(w, g); ei != ei_end; ++ei) { + v = target(*ei, g); + put(degree, v, get(degree, v) - 1); + + if (colors[get(vertex_map, v)] == 1) { + percolate_up(get(vertex_map, v), i); + } + } + + colors[get(vertex_map, w)] = 0; + i++; + } + } + + template + void examine_vertex(Vertex u, const Graph&) { + + *(*permutation)++ = u; + index_begin = Qptr->size(); + + } + protected: + + + //this function replaces pop_heap, and tracks state information + template + void percolate_down(int offset){ + typedef typename std::deque::reverse_iterator reverse_iterator; + + int heap_last = index_begin + offset; + int heap_first = Qptr->size() - 1; + + //pop_heap functionality: + //swap first, last + std::swap((*Qptr)[heap_last], (*Qptr)[heap_first]); + + //swap in the location queue + std::swap(Qlocation[heap_first], Qlocation[heap_last]); + + //set drifter, children + int drifter = heap_first; + int drifter_heap = Qptr->size() - drifter; + + int right_child_heap = drifter_heap * 2 + 1; + int right_child = Qptr->size() - right_child_heap; + + int left_child_heap = drifter_heap * 2; + int left_child = Qptr->size() - left_child_heap; + + //check that we are staying in the heap + bool valid = (right_child < heap_last) ? false : true; + + //pick smallest child of drifter, and keep in mind there might only be left child + int smallest_child = (valid && get(degree, (*Qptr)[left_child]) > get(degree,(*Qptr)[right_child])) ? + right_child : left_child; + + while(valid && smallest_child < heap_last && comp((*Qptr)[drifter], (*Qptr)[smallest_child])){ + + //if smallest child smaller than drifter, swap them + std::swap((*Qptr)[smallest_child], (*Qptr)[drifter]); + std::swap(Qlocation[drifter], Qlocation[smallest_child]); + + //update the values, run again, as necessary + drifter = smallest_child; + drifter_heap = Qptr->size() - drifter; + + right_child_heap = drifter_heap * 2 + 1; + right_child = Qptr->size() - right_child_heap; + + left_child_heap = drifter_heap * 2; + left_child = Qptr->size() - left_child_heap; + + valid = (right_child < heap_last) ? false : true; + + smallest_child = (valid && get(degree, (*Qptr)[left_child]) > get(degree,(*Qptr)[right_child])) ? + right_child : left_child; + } + + } + + + + // this is like percolate down, but we always compare against the + // parent, as there is only a single choice + template + void percolate_up(int vertex, int offset){ + + int child_location = Qlocation[vertex]; + int heap_child_location = Qptr->size() - child_location; + int heap_parent_location = (int)(heap_child_location/2); + unsigned parent_location = Qptr->size() - heap_parent_location; + + bool valid = (heap_parent_location != 0 && child_location > index_begin + offset && + parent_location < Qptr->size()); + + while(valid && comp((*Qptr)[child_location], (*Qptr)[parent_location])){ + + //swap in the heap + std::swap((*Qptr)[child_location], (*Qptr)[parent_location]); + + //swap in the location queue + std::swap(Qlocation[child_location], Qlocation[parent_location]); + + child_location = parent_location; + heap_child_location = heap_parent_location; + heap_parent_location = (int)(heap_child_location/2); + parent_location = Qptr->size() - heap_parent_location; + valid = (heap_parent_location != 0 && child_location > index_begin + offset); + } + } + + OutputIterator *permutation; + int index_begin; + Buffer *Qptr; + PseudoDegreeMap degree; + Compare comp; + std::vector Qlocation; + VecMap colors; + VertexIndexMap vertex_map; + }; + + + } // namespace detail + + + template + OutputIterator + king_ordering(const Graph& g, + std::deque< typename graph_traits::vertex_descriptor > + vertex_queue, + OutputIterator permutation, + ColorMap color, DegreeMap degree, + VertexIndexMap index_map) + { + typedef typename property_traits::value_type ds_type; + typedef typename property_traits::value_type ColorValue; + typedef color_traits Color; + typedef typename graph_traits::vertex_descriptor Vertex; + typedef iterator_property_map::iterator, VertexIndexMap, ds_type, ds_type&> PseudoDegreeMap; + typedef indirect_cmp > Compare; + typedef typename boost::sparse::sparse_ordering_queue queue; + typedef typename detail::bfs_king_visitor, VertexIndexMap > Visitor; + typedef typename graph_traits::vertices_size_type + vertices_size_type; + std::vector pseudo_degree_vec(num_vertices(g)); + PseudoDegreeMap pseudo_degree(pseudo_degree_vec.begin(), index_map); + + typename graph_traits::vertex_iterator ui, ui_end; + queue Q; + // Copy degree to pseudo_degree + // initialize the color map + for (tie(ui, ui_end) = vertices(g); ui != ui_end; ++ui){ + put(pseudo_degree, *ui, get(degree, *ui)); + put(color, *ui, Color::white()); + } + + Compare comp(pseudo_degree); + std::vector colors(num_vertices(g)); + + for(vertices_size_type i = 0; i < num_vertices(g); i++) + colors[i] = 0; + + std::vector loc(num_vertices(g)); + + //create the visitor + Visitor vis(&permutation, &Q, comp, pseudo_degree, loc, colors, index_map); + + while( !vertex_queue.empty() ) { + Vertex s = vertex_queue.front(); + vertex_queue.pop_front(); + + //call BFS with visitor + breadth_first_visit(g, s, Q, vis, color); + } + + return permutation; + } + + + // This is the case where only a single starting vertex is supplied. + template + OutputIterator + king_ordering(const Graph& g, + typename graph_traits::vertex_descriptor s, + OutputIterator permutation, + ColorMap color, DegreeMap degree, VertexIndexMap index_map) + { + + std::deque< typename graph_traits::vertex_descriptor > vertex_queue; + vertex_queue.push_front( s ); + return king_ordering(g, vertex_queue, permutation, color, degree, + index_map); + } + + + template < class Graph, class OutputIterator, + class ColorMap, class DegreeMap, class VertexIndexMap> + OutputIterator + king_ordering(const Graph& G, OutputIterator permutation, + ColorMap color, DegreeMap degree, VertexIndexMap index_map) + { + if (vertices(G).first == vertices(G).second) + return permutation; + + typedef typename boost::graph_traits::vertex_descriptor Vertex; + typedef typename boost::graph_traits::vertex_iterator VerIter; + typedef typename property_traits::value_type ColorValue; + typedef color_traits Color; + + std::deque vertex_queue; + + // Mark everything white + BGL_FORALL_VERTICES_T(v, G, Graph) put(color, v, Color::white()); + + // Find one vertex from each connected component + BGL_FORALL_VERTICES_T(v, G, Graph) { + if (get(color, v) == Color::white()) { + depth_first_visit(G, v, dfs_visitor<>(), color); + vertex_queue.push_back(v); + } + } + + // Find starting nodes for all vertices + // TBD: How to do this with a directed graph? + for (typename std::deque::iterator i = vertex_queue.begin(); + i != vertex_queue.end(); ++i) + *i = find_starting_node(G, *i, color, degree); + + return king_ordering(G, vertex_queue, permutation, color, degree, + index_map); + } + + template + OutputIterator + king_ordering(const Graph& G, OutputIterator permutation, + VertexIndexMap index_map) + { + if (vertices(G).first == vertices(G).second) + return permutation; + + typedef out_degree_property_map DegreeMap; + std::vector colors(num_vertices(G)); + return king_ordering(G, permutation, + make_iterator_property_map(&colors[0], index_map, + colors[0]), + make_out_degree_map(G), index_map); + } + + template + inline OutputIterator + king_ordering(const Graph& G, OutputIterator permutation) + { return king_ordering(G, permutation, get(vertex_index, G)); } + +} // namespace boost + + +#endif // BOOST_GRAPH_KING_HPP