diff -r 666f914201fb -r 2fe1408b6811 epoc32/include/stdapis/boost/graph/kamada_kawai_spring_layout.hpp --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/epoc32/include/stdapis/boost/graph/kamada_kawai_spring_layout.hpp Tue Mar 16 16:12:26 2010 +0000 @@ -0,0 +1,542 @@ +// Copyright 2004 The Trustees of Indiana University. + +// 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) + +// Authors: Douglas Gregor +// Andrew Lumsdaine +#ifndef BOOST_GRAPH_KAMADA_KAWAI_SPRING_LAYOUT_HPP +#define BOOST_GRAPH_KAMADA_KAWAI_SPRING_LAYOUT_HPP + +#include <boost/graph/graph_traits.hpp> +#include <boost/graph/johnson_all_pairs_shortest.hpp> +#include <boost/type_traits/is_convertible.hpp> +#include <utility> +#include <iterator> +#include <vector> +#include <boost/limits.hpp> +#include <cmath> + +namespace boost { + namespace detail { namespace graph { + /** + * Denotes an edge or display area side length used to scale a + * Kamada-Kawai drawing. + */ + template<bool Edge, typename T> + struct edge_or_side + { + explicit edge_or_side(T value) : value(value) {} + + T value; + }; + + /** + * Compute the edge length from an edge length. This is trivial. + */ + template<typename Graph, typename DistanceMap, typename IndexMap, + typename T> + T compute_edge_length(const Graph&, DistanceMap, IndexMap, + edge_or_side<true, T> length) + { return length.value; } + + /** + * Compute the edge length based on the display area side + length. We do this by dividing the side length by the largest + shortest distance between any two vertices in the graph. + */ + template<typename Graph, typename DistanceMap, typename IndexMap, + typename T> + T + compute_edge_length(const Graph& g, DistanceMap distance, IndexMap index, + edge_or_side<false, T> length) + { + T result(0); + + typedef typename graph_traits<Graph>::vertex_iterator vertex_iterator; + + for (vertex_iterator ui = vertices(g).first, end = vertices(g).second; + ui != end; ++ui) { + vertex_iterator vi = ui; + for (++vi; vi != end; ++vi) { + T dij = distance[get(index, *ui)][get(index, *vi)]; + if (dij > result) result = dij; + } + } + return length.value / result; + } + + /** + * Implementation of the Kamada-Kawai spring layout algorithm. + */ + template<typename Graph, typename PositionMap, typename WeightMap, + typename EdgeOrSideLength, typename Done, + typename VertexIndexMap, typename DistanceMatrix, + typename SpringStrengthMatrix, typename PartialDerivativeMap> + struct kamada_kawai_spring_layout_impl + { + typedef typename property_traits<WeightMap>::value_type weight_type; + typedef std::pair<weight_type, weight_type> deriv_type; + typedef typename graph_traits<Graph>::vertex_iterator vertex_iterator; + typedef typename graph_traits<Graph>::vertex_descriptor + vertex_descriptor; + + kamada_kawai_spring_layout_impl( + const Graph& g, + PositionMap position, + WeightMap weight, + EdgeOrSideLength edge_or_side_length, + Done done, + weight_type spring_constant, + VertexIndexMap index, + DistanceMatrix distance, + SpringStrengthMatrix spring_strength, + PartialDerivativeMap partial_derivatives) + : g(g), position(position), weight(weight), + edge_or_side_length(edge_or_side_length), done(done), + spring_constant(spring_constant), index(index), distance(distance), + spring_strength(spring_strength), + partial_derivatives(partial_derivatives) {} + + // Compute contribution of vertex i to the first partial + // derivatives (dE/dx_m, dE/dy_m) (for vertex m) + deriv_type + compute_partial_derivative(vertex_descriptor m, vertex_descriptor i) + { +#ifndef BOOST_NO_STDC_NAMESPACE + using std::sqrt; +#endif // BOOST_NO_STDC_NAMESPACE + + deriv_type result(0, 0); + if (i != m) { + weight_type x_diff = position[m].x - position[i].x; + weight_type y_diff = position[m].y - position[i].y; + weight_type dist = sqrt(x_diff * x_diff + y_diff * y_diff); + result.first = spring_strength[get(index, m)][get(index, i)] + * (x_diff - distance[get(index, m)][get(index, i)]*x_diff/dist); + result.second = spring_strength[get(index, m)][get(index, i)] + * (y_diff - distance[get(index, m)][get(index, i)]*y_diff/dist); + } + + return result; + } + + // Compute partial derivatives dE/dx_m and dE/dy_m + deriv_type + compute_partial_derivatives(vertex_descriptor m) + { +#ifndef BOOST_NO_STDC_NAMESPACE + using std::sqrt; +#endif // BOOST_NO_STDC_NAMESPACE + + deriv_type result(0, 0); + + // TBD: looks like an accumulate to me + std::pair<vertex_iterator, vertex_iterator> verts = vertices(g); + for (/* no init */; verts.first != verts.second; ++verts.first) { + vertex_descriptor i = *verts.first; + deriv_type deriv = compute_partial_derivative(m, i); + result.first += deriv.first; + result.second += deriv.second; + } + + return result; + } + + // The actual Kamada-Kawai spring layout algorithm implementation + bool run() + { +#ifndef BOOST_NO_STDC_NAMESPACE + using std::sqrt; +#endif // BOOST_NO_STDC_NAMESPACE + + // Compute d_{ij} and place it in the distance matrix + if (!johnson_all_pairs_shortest_paths(g, distance, index, weight, + weight_type(0))) + return false; + + // Compute L based on side length (if needed), or retrieve L + weight_type edge_length = + detail::graph::compute_edge_length(g, distance, index, + edge_or_side_length); + + // Compute l_{ij} and k_{ij} + const weight_type K = spring_constant; + vertex_iterator ui, end = vertices(g).second; + for (ui = vertices(g).first; ui != end; ++ui) { + vertex_iterator vi = ui; + for (++vi; vi != end; ++vi) { + weight_type dij = distance[get(index, *ui)][get(index, *vi)]; + if (dij == (std::numeric_limits<weight_type>::max)()) + return false; + distance[get(index, *ui)][get(index, *vi)] = edge_length * dij; + distance[get(index, *vi)][get(index, *ui)] = edge_length * dij; + spring_strength[get(index, *ui)][get(index, *vi)] = K/(dij*dij); + spring_strength[get(index, *vi)][get(index, *ui)] = K/(dij*dij); + } + } + + // Compute Delta_i and find max + vertex_descriptor p = *vertices(g).first; + weight_type delta_p(0); + + for (ui = vertices(g).first; ui != end; ++ui) { + deriv_type deriv = compute_partial_derivatives(*ui); + put(partial_derivatives, *ui, deriv); + + weight_type delta = + sqrt(deriv.first*deriv.first + deriv.second*deriv.second); + + if (delta > delta_p) { + p = *ui; + delta_p = delta; + } + } + + while (!done(delta_p, p, g, true)) { + // The contribution p makes to the partial derivatives of + // each vertex. Computing this (at O(n) cost) allows us to + // update the delta_i values in O(n) time instead of O(n^2) + // time. + std::vector<deriv_type> p_partials(num_vertices(g)); + for (ui = vertices(g).first; ui != end; ++ui) { + vertex_descriptor i = *ui; + p_partials[get(index, i)] = compute_partial_derivative(i, p); + } + + do { + // Compute the 4 elements of the Jacobian + weight_type dE_dx_dx = 0, dE_dx_dy = 0, dE_dy_dx = 0, dE_dy_dy = 0; + for (ui = vertices(g).first; ui != end; ++ui) { + vertex_descriptor i = *ui; + if (i != p) { + weight_type x_diff = position[p].x - position[i].x; + weight_type y_diff = position[p].y - position[i].y; + weight_type dist = sqrt(x_diff * x_diff + y_diff * y_diff); + weight_type dist_cubed = dist * dist * dist; + weight_type k_mi = spring_strength[get(index,p)][get(index,i)]; + weight_type l_mi = distance[get(index, p)][get(index, i)]; + dE_dx_dx += k_mi * (1 - (l_mi * y_diff * y_diff)/dist_cubed); + dE_dx_dy += k_mi * l_mi * x_diff * y_diff / dist_cubed; + dE_dy_dx += k_mi * l_mi * x_diff * y_diff / dist_cubed; + dE_dy_dy += k_mi * (1 - (l_mi * x_diff * x_diff)/dist_cubed); + } + } + + // Solve for delta_x and delta_y + weight_type dE_dx = get(partial_derivatives, p).first; + weight_type dE_dy = get(partial_derivatives, p).second; + + weight_type delta_x = + (dE_dx_dy * dE_dy - dE_dy_dy * dE_dx) + / (dE_dx_dx * dE_dy_dy - dE_dx_dy * dE_dy_dx); + + weight_type delta_y = + (dE_dx_dx * dE_dy - dE_dy_dx * dE_dx) + / (dE_dy_dx * dE_dx_dy - dE_dx_dx * dE_dy_dy); + + + // Move p by (delta_x, delta_y) + position[p].x += delta_x; + position[p].y += delta_y; + + // Recompute partial derivatives and delta_p + deriv_type deriv = compute_partial_derivatives(p); + put(partial_derivatives, p, deriv); + + delta_p = + sqrt(deriv.first*deriv.first + deriv.second*deriv.second); + } while (!done(delta_p, p, g, false)); + + // Select new p by updating each partial derivative and delta + vertex_descriptor old_p = p; + for (ui = vertices(g).first; ui != end; ++ui) { + deriv_type old_deriv_p = p_partials[get(index, *ui)]; + deriv_type old_p_partial = + compute_partial_derivative(*ui, old_p); + deriv_type deriv = get(partial_derivatives, *ui); + + deriv.first += old_p_partial.first - old_deriv_p.first; + deriv.second += old_p_partial.second - old_deriv_p.second; + + put(partial_derivatives, *ui, deriv); + weight_type delta = + sqrt(deriv.first*deriv.first + deriv.second*deriv.second); + + if (delta > delta_p) { + p = *ui; + delta_p = delta; + } + } + } + + return true; + } + + const Graph& g; + PositionMap position; + WeightMap weight; + EdgeOrSideLength edge_or_side_length; + Done done; + weight_type spring_constant; + VertexIndexMap index; + DistanceMatrix distance; + SpringStrengthMatrix spring_strength; + PartialDerivativeMap partial_derivatives; + }; + } } // end namespace detail::graph + + /// States that the given quantity is an edge length. + template<typename T> + inline detail::graph::edge_or_side<true, T> + edge_length(T x) + { return detail::graph::edge_or_side<true, T>(x); } + + /// States that the given quantity is a display area side length. + template<typename T> + inline detail::graph::edge_or_side<false, T> + side_length(T x) + { return detail::graph::edge_or_side<false, T>(x); } + + /** + * \brief Determines when to terminate layout of a particular graph based + * on a given relative tolerance. + */ + template<typename T = double> + struct layout_tolerance + { + layout_tolerance(const T& tolerance = T(0.001)) + : tolerance(tolerance), last_energy((std::numeric_limits<T>::max)()), + last_local_energy((std::numeric_limits<T>::max)()) { } + + template<typename Graph> + bool + operator()(T delta_p, + typename boost::graph_traits<Graph>::vertex_descriptor p, + const Graph& g, + bool global) + { + if (global) { + if (last_energy == (std::numeric_limits<T>::max)()) { + last_energy = delta_p; + return false; + } + + T diff = last_energy - delta_p; + if (diff < T(0)) diff = -diff; + bool done = (delta_p == T(0) || diff / last_energy < tolerance); + last_energy = delta_p; + return done; + } else { + if (last_local_energy == (std::numeric_limits<T>::max)()) { + last_local_energy = delta_p; + return delta_p == T(0); + } + + T diff = last_local_energy - delta_p; + bool done = (delta_p == T(0) || (diff / last_local_energy) < tolerance); + last_local_energy = delta_p; + return done; + } + } + + private: + T tolerance; + T last_energy; + T last_local_energy; + }; + + /** \brief Kamada-Kawai spring layout for undirected graphs. + * + * This algorithm performs graph layout (in two dimensions) for + * connected, undirected graphs. It operates by relating the layout + * of graphs to a dynamic spring system and minimizing the energy + * within that system. The strength of a spring between two vertices + * is inversely proportional to the square of the shortest distance + * (in graph terms) between those two vertices. Essentially, + * vertices that are closer in the graph-theoretic sense (i.e., by + * following edges) will have stronger springs and will therefore be + * placed closer together. + * + * Prior to invoking this algorithm, it is recommended that the + * vertices be placed along the vertices of a regular n-sided + * polygon. + * + * \param g (IN) must be a model of Vertex List Graph, Edge List + * Graph, and Incidence Graph and must be undirected. + * + * \param position (OUT) must be a model of Lvalue Property Map, + * where the value type is a class containing fields @c x and @c y + * that will be set to the @c x and @c y coordinates of each vertex. + * + * \param weight (IN) must be a model of Readable Property Map, + * which provides the weight of each edge in the graph @p g. + * + * \param edge_or_side_length (IN) provides either the unit length + * @c e of an edge in the layout or the length of a side @c s of the + * display area, and must be either @c boost::edge_length(e) or @c + * boost::side_length(s), respectively. + * + * \param done (IN) is a 4-argument function object that is passed + * the current value of delta_p (i.e., the energy of vertex @p p), + * the vertex @p p, the graph @p g, and a boolean flag indicating + * whether @p delta_p is the maximum energy in the system (when @c + * true) or the energy of the vertex being moved. Defaults to @c + * layout_tolerance instantiated over the value type of the weight + * map. + * + * \param spring_constant (IN) is the constant multiplied by each + * spring's strength. Larger values create systems with more energy + * that can take longer to stabilize; smaller values create systems + * with less energy that stabilize quickly but do not necessarily + * result in pleasing layouts. The default value is 1. + * + * \param index (IN) is a mapping from vertices to index values + * between 0 and @c num_vertices(g). The default is @c + * get(vertex_index,g). + * + * \param distance (UTIL/OUT) will be used to store the distance + * from every vertex to every other vertex, which is computed in the + * first stages of the algorithm. This value's type must be a model + * of BasicMatrix with value type equal to the value type of the + * weight map. The default is a a vector of vectors. + * + * \param spring_strength (UTIL/OUT) will be used to store the + * strength of the spring between every pair of vertices. This + * value's type must be a model of BasicMatrix with value type equal + * to the value type of the weight map. The default is a a vector of + * vectors. + * + * \param partial_derivatives (UTIL) will be used to store the + * partial derivates of each vertex with respect to the @c x and @c + * y coordinates. This must be a Read/Write Property Map whose value + * type is a pair with both types equivalent to the value type of + * the weight map. The default is an iterator property map. + * + * \returns @c true if layout was successful or @c false if a + * negative weight cycle was detected. + */ + template<typename Graph, typename PositionMap, typename WeightMap, + typename T, bool EdgeOrSideLength, typename Done, + typename VertexIndexMap, typename DistanceMatrix, + typename SpringStrengthMatrix, typename PartialDerivativeMap> + bool + kamada_kawai_spring_layout( + const Graph& g, + PositionMap position, + WeightMap weight, + detail::graph::edge_or_side<EdgeOrSideLength, T> edge_or_side_length, + Done done, + typename property_traits<WeightMap>::value_type spring_constant, + VertexIndexMap index, + DistanceMatrix distance, + SpringStrengthMatrix spring_strength, + PartialDerivativeMap partial_derivatives) + { + BOOST_STATIC_ASSERT((is_convertible< + typename graph_traits<Graph>::directed_category*, + undirected_tag* + >::value)); + + detail::graph::kamada_kawai_spring_layout_impl< + Graph, PositionMap, WeightMap, + detail::graph::edge_or_side<EdgeOrSideLength, T>, Done, VertexIndexMap, + DistanceMatrix, SpringStrengthMatrix, PartialDerivativeMap> + alg(g, position, weight, edge_or_side_length, done, spring_constant, + index, distance, spring_strength, partial_derivatives); + return alg.run(); + } + + /** + * \overload + */ + template<typename Graph, typename PositionMap, typename WeightMap, + typename T, bool EdgeOrSideLength, typename Done, + typename VertexIndexMap> + bool + kamada_kawai_spring_layout( + const Graph& g, + PositionMap position, + WeightMap weight, + detail::graph::edge_or_side<EdgeOrSideLength, T> edge_or_side_length, + Done done, + typename property_traits<WeightMap>::value_type spring_constant, + VertexIndexMap index) + { + typedef typename property_traits<WeightMap>::value_type weight_type; + + typename graph_traits<Graph>::vertices_size_type n = num_vertices(g); + typedef std::vector<weight_type> weight_vec; + + std::vector<weight_vec> distance(n, weight_vec(n)); + std::vector<weight_vec> spring_strength(n, weight_vec(n)); + std::vector<std::pair<weight_type, weight_type> > partial_derivatives(n); + + return + kamada_kawai_spring_layout( + g, position, weight, edge_or_side_length, done, spring_constant, index, + distance.begin(), + spring_strength.begin(), + make_iterator_property_map(partial_derivatives.begin(), index, + std::pair<weight_type, weight_type>())); + } + + /** + * \overload + */ + template<typename Graph, typename PositionMap, typename WeightMap, + typename T, bool EdgeOrSideLength, typename Done> + bool + kamada_kawai_spring_layout( + const Graph& g, + PositionMap position, + WeightMap weight, + detail::graph::edge_or_side<EdgeOrSideLength, T> edge_or_side_length, + Done done, + typename property_traits<WeightMap>::value_type spring_constant) + { + return kamada_kawai_spring_layout(g, position, weight, edge_or_side_length, + done, spring_constant, + get(vertex_index, g)); + } + + /** + * \overload + */ + template<typename Graph, typename PositionMap, typename WeightMap, + typename T, bool EdgeOrSideLength, typename Done> + bool + kamada_kawai_spring_layout( + const Graph& g, + PositionMap position, + WeightMap weight, + detail::graph::edge_or_side<EdgeOrSideLength, T> edge_or_side_length, + Done done) + { + typedef typename property_traits<WeightMap>::value_type weight_type; + return kamada_kawai_spring_layout(g, position, weight, edge_or_side_length, + done, weight_type(1)); + } + + /** + * \overload + */ + template<typename Graph, typename PositionMap, typename WeightMap, + typename T, bool EdgeOrSideLength> + bool + kamada_kawai_spring_layout( + const Graph& g, + PositionMap position, + WeightMap weight, + detail::graph::edge_or_side<EdgeOrSideLength, T> edge_or_side_length) + { + typedef typename property_traits<WeightMap>::value_type weight_type; + return kamada_kawai_spring_layout(g, position, weight, edge_or_side_length, + layout_tolerance<weight_type>(), + weight_type(1.0), + get(vertex_index, g)); + } +} // end namespace boost + +#endif // BOOST_GRAPH_KAMADA_KAWAI_SPRING_LAYOUT_HPP