+++ /dev/null
-/*
-* Copyright (c) 2003, the JUNG Project and the Regents of the University
-* of California
-* All rights reserved.
-*
-* This software is open-source under the BSD license; see either
-* "license.txt" or
-* http://jung.sourceforge.net/license.txt for a description.
-*/
-package edu.uci.ics.jung.algorithms.shortestpath;
-import java.util.Collection;
-
-import org.apache.commons.collections15.Transformer;
-
-import edu.uci.ics.jung.algorithms.scoring.ClosenessCentrality;
-import edu.uci.ics.jung.algorithms.scoring.util.VertexScoreTransformer;
-import edu.uci.ics.jung.graph.Hypergraph;
-
-/**
- * Statistics relating to vertex-vertex distances in a graph.
- *
- * <p>Formerly known as <code>GraphStatistics</code> in JUNG 1.x.</p>
- *
- * @author Scott White
- * @author Joshua O'Madadhain
- */
-public class DistanceStatistics
-{
- /**
- * For each vertex <code>v</code> in <code>graph</code>,
- * calculates the average shortest path length from <code>v</code>
- * to all other vertices in <code>graph</code> using the metric
- * specified by <code>d</code>, and returns the results in a
- * <code>Map</code> from vertices to <code>Double</code> values.
- * If there exists an ordered pair <code><u,v></code>
- * for which <code>d.getDistance(u,v)</code> returns <code>null</code>,
- * then the average distance value for <code>u</code> will be stored
- * as <code>Double.POSITIVE_INFINITY</code>).
- *
- * <p>Does not include self-distances (path lengths from <code>v</code>
- * to <code>v</code>).
- *
- * <p>To calculate the average distances, ignoring edge weights if any:
- * <pre>
- * Map distances = DistanceStatistics.averageDistances(g, new UnweightedShortestPath(g));
- * </pre>
- * To calculate the average distances respecting edge weights:
- * <pre>
- * DijkstraShortestPath dsp = new DijkstraShortestPath(g, nev);
- * Map distances = DistanceStatistics.averageDistances(g, dsp);
- * </pre>
- * where <code>nev</code> is an instance of <code>Transformer</code> that
- * is used to fetch the weight for each edge.
- *
- * @see edu.uci.ics.jung.algorithms.shortestpath.UnweightedShortestPath
- * @see edu.uci.ics.jung.algorithms.shortestpath.DijkstraDistance
- */
- public static <V,E> Transformer<V,Double> averageDistances(Hypergraph<V,E> graph, Distance<V> d)
- {
- final ClosenessCentrality<V,E> cc = new ClosenessCentrality<V,E>(graph, d);
- return new VertexScoreTransformer<V, Double>(cc);
- }
-
- /**
- * For each vertex <code>v</code> in <code>g</code>,
- * calculates the average shortest path length from <code>v</code>
- * to all other vertices in <code>g</code>, ignoring edge weights.
- * @see #diameter(Hypergraph)
- * @see edu.uci.ics.jung.algorithms.scoring.ClosenessCentrality
- */
- public static <V,E> Transformer<V, Double> averageDistances(Hypergraph<V,E> g)
- {
- final ClosenessCentrality<V,E> cc = new ClosenessCentrality<V,E>(g,
- new UnweightedShortestPath<V,E>(g));
- return new VertexScoreTransformer<V, Double>(cc);
- }
-
- /**
- * Returns the diameter of <code>g</code> using the metric
- * specified by <code>d</code>. The diameter is defined to be
- * the maximum, over all pairs of vertices <code>u,v</code>,
- * of the length of the shortest path from <code>u</code> to
- * <code>v</code>. If the graph is disconnected (that is, not
- * all pairs of vertices are reachable from one another), the
- * value returned will depend on <code>use_max</code>:
- * if <code>use_max == true</code>, the value returned
- * will be the the maximum shortest path length over all pairs of <b>connected</b>
- * vertices; otherwise it will be <code>Double.POSITIVE_INFINITY</code>.
- */
- public static <V, E> double diameter(Hypergraph<V,E> g, Distance<V> d, boolean use_max)
- {
- double diameter = 0;
- Collection<V> vertices = g.getVertices();
- for(V v : vertices) {
- for(V w : vertices) {
-
- if (v.equals(w) == false) // don't include self-distances
- {
- Number dist = d.getDistance(v, w);
- if (dist == null)
- {
- if (!use_max)
- return Double.POSITIVE_INFINITY;
- }
- else
- diameter = Math.max(diameter, dist.doubleValue());
- }
- }
- }
- return diameter;
- }
-
- /**
- * Returns the diameter of <code>g</code> using the metric
- * specified by <code>d</code>. The diameter is defined to be
- * the maximum, over all pairs of vertices <code>u,v</code>,
- * of the length of the shortest path from <code>u</code> to
- * <code>v</code>, or <code>Double.POSITIVE_INFINITY</code>
- * if any of these distances do not exist.
- * @see #diameter(Hypergraph, Distance, boolean)
- */
- public static <V, E> double diameter(Hypergraph<V,E> g, Distance<V> d)
- {
- return diameter(g, d, false);
- }
-
- /**
- * Returns the diameter of <code>g</code>, ignoring edge weights.
- * @see #diameter(Hypergraph, Distance, boolean)
- */
- public static <V, E> double diameter(Hypergraph<V,E> g)
- {
- return diameter(g, new UnweightedShortestPath<V,E>(g));
- }
-
-}
Code Review / controller.git / blobdiff