/*
Copyright 2008-2011 Gephi
Authors : Patick J. McSweeney <pjmcswee@syr.edu>, Sebastien Heymann <seb@gephi.org>
Website : http://www.gephi.org
This file is part of Gephi.
DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
Copyright 2011 Gephi Consortium. All rights reserved.
The contents of this file are subject to the terms of either the GNU
General Public License Version 3 only ("GPL") or the Common
Development and Distribution License("CDDL") (collectively, the
"License"). You may not use this file except in compliance with the
License. You can obtain a copy of the License at
http://gephi.org/about/legal/license-notice/
or /cddl-1.0.txt and /gpl-3.0.txt. See the License for the
specific language governing permissions and limitations under the
License. When distributing the software, include this License Header
Notice in each file and include the License files at
/cddl-1.0.txt and /gpl-3.0.txt. If applicable, add the following below the
License Header, with the fields enclosed by brackets [] replaced by
your own identifying information:
"Portions Copyrighted [year] [name of copyright owner]"
If you wish your version of this file to be governed by only the CDDL
or only the GPL Version 3, indicate your decision by adding
"[Contributor] elects to include this software in this distribution
under the [CDDL or GPL Version 3] license." If you do not indicate a
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your version of this file under either the CDDL, the GPL Version 3 or
to extend the choice of license to its licensees as provided above.
However, if you add GPL Version 3 code and therefore, elected the GPL
Version 3 license, then the option applies only if the new code is
made subject to such option by the copyright holder.
Contributor(s): Thomas Aynaud <taynaud@gmail.com>
Portions Copyrighted 2011 Gephi Consortium.
*/
package org.gephi.statistics.plugin;
import java.text.DecimalFormat;
import java.text.NumberFormat;
import java.util.*;
import org.gephi.attribute.api.AttributeModel;
import org.gephi.attribute.api.Column;
import org.gephi.attribute.api.Table;
import org.gephi.graph.api.Graph;
import org.gephi.graph.api.GraphModel;
import org.gephi.graph.api.Node;
import org.gephi.statistics.spi.Statistics;
import org.gephi.utils.longtask.spi.LongTask;
import org.gephi.utils.progress.Progress;
import org.gephi.utils.progress.ProgressTicket;
import org.jfree.chart.ChartFactory;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.plot.PlotOrientation;
import org.jfree.data.xy.XYSeries;
import org.jfree.data.xy.XYSeriesCollection;
/**
*
* @author pjmcswee
*/
public class Modularity implements Statistics, LongTask {
public static final String MODULARITY_CLASS = "modularity_class";
private ProgressTicket progress;
private boolean isCanceled;
private CommunityStructure structure;
private double modularity;
private double modularityResolution;
private boolean isRandomized = false;
private boolean useWeight = true;
private double resolution = 1.;
public void setRandom(boolean isRandomized) {
this.isRandomized = isRandomized;
}
public boolean getRandom() {
return isRandomized;
}
public void setUseWeight(boolean useWeight) {
this.useWeight = useWeight;
}
public boolean getUseWeight() {
return useWeight;
}
public void setResolution(double resolution) {
this.resolution = resolution;
}
public double getResolution() {
return resolution;
}
@Override
public boolean cancel() {
this.isCanceled = true;
return true;
}
@Override
public void setProgressTicket(ProgressTicket progressTicket) {
this.progress = progressTicket;
}
class ModEdge {
int source;
int target;
float weight;
public ModEdge(int s, int t, float w) {
source = s;
target = t;
weight = w;
}
}
class CommunityStructure {
HashMap<Modularity.Community, Float>[] nodeConnectionsWeight;
HashMap<Modularity.Community, Integer>[] nodeConnectionsCount;
HashMap<Node, Integer> map;
Community[] nodeCommunities;
Graph graph;
double[] weights;
double graphWeightSum;
LinkedList<ModEdge>[] topology;
LinkedList<Community> communities;
int N;
HashMap<Integer, Community> invMap;
CommunityStructure(Graph hgraph) {
this.graph = hgraph;
N = hgraph.getNodeCount();
invMap = new HashMap<Integer, Community>();
nodeConnectionsWeight = new HashMap[N];
nodeConnectionsCount = new HashMap[N];
nodeCommunities = new Community[N];
map = new HashMap<Node, Integer>();
topology = new LinkedList[N];
communities = new LinkedList<Community>();
int index = 0;
weights = new double[N];
for (Node node : hgraph.getNodes()) {
map.put(node, index);
nodeCommunities[index] = new Community(this);
nodeConnectionsWeight[index] = new HashMap<Community, Float>();
nodeConnectionsCount[index] = new HashMap<Community, Integer>();
weights[index] = 0;
nodeCommunities[index].seed(index);
Community hidden = new Community(structure);
hidden.nodes.add(index);
invMap.put(index, hidden);
communities.add(nodeCommunities[index]);
index++;
if (isCanceled) {
return;
}
}
for (Node node : hgraph.getNodes()) {
int node_index = map.get(node);
topology[node_index] = new LinkedList<ModEdge>();
for (Node neighbor : hgraph.getNeighbors(node)) {
if (node == neighbor) {
continue;
}
int neighbor_index = map.get(neighbor);
float weight = 1;
if (useWeight) {
weight = (float) hgraph.getEdge(node, neighbor).getWeight();
}
weights[node_index] += weight;
Modularity.ModEdge me = new ModEdge(node_index, neighbor_index, weight);
topology[node_index].add(me);
Community adjCom = nodeCommunities[neighbor_index];
nodeConnectionsWeight[node_index].put(adjCom, weight);
nodeConnectionsCount[node_index].put(adjCom, 1);
nodeCommunities[node_index].connectionsWeight.put(adjCom, weight);
nodeCommunities[node_index].connectionsCount.put(adjCom, 1);
nodeConnectionsWeight[neighbor_index].put(nodeCommunities[node_index], weight);
nodeConnectionsCount[neighbor_index].put(nodeCommunities[node_index], 1);
nodeCommunities[neighbor_index].connectionsWeight.put(nodeCommunities[node_index], weight);
nodeCommunities[neighbor_index].connectionsCount.put(nodeCommunities[node_index], 1);
graphWeightSum += weight;
}
if (isCanceled) {
return;
}
}
graphWeightSum /= 2.0;
}
private void addNodeTo(int node, Community to) {
to.add(new Integer(node));
nodeCommunities[node] = to;
for (ModEdge e : topology[node]) {
int neighbor = e.target;
////////
//Remove Node Connection to this community
Float neighEdgesTo = nodeConnectionsWeight[neighbor].get(to);
if (neighEdgesTo == null) {
nodeConnectionsWeight[neighbor].put(to, e.weight);
} else {
nodeConnectionsWeight[neighbor].put(to, neighEdgesTo + e.weight);
}
Integer neighCountEdgesTo = nodeConnectionsCount[neighbor].get(to);
if (neighCountEdgesTo == null) {
nodeConnectionsCount[neighbor].put(to, 1);
} else {
nodeConnectionsCount[neighbor].put(to, neighCountEdgesTo + 1);
}
///////////////////
Modularity.Community adjCom = nodeCommunities[neighbor];
Float wEdgesto = adjCom.connectionsWeight.get(to);
if (wEdgesto == null) {
adjCom.connectionsWeight.put(to, e.weight);
} else {
adjCom.connectionsWeight.put(to, wEdgesto + e.weight);
}
Integer cEdgesto = adjCom.connectionsCount.get(to);
if (cEdgesto == null) {
adjCom.connectionsCount.put(to, 1);
} else {
adjCom.connectionsCount.put(to, cEdgesto + 1);
}
Float nodeEdgesTo = nodeConnectionsWeight[node].get(adjCom);
if (nodeEdgesTo == null) {
nodeConnectionsWeight[node].put(adjCom, e.weight);
} else {
nodeConnectionsWeight[node].put(adjCom, nodeEdgesTo + e.weight);
}
Integer nodeCountEdgesTo = nodeConnectionsCount[node].get(adjCom);
if (nodeCountEdgesTo == null) {
nodeConnectionsCount[node].put(adjCom, 1);
} else {
nodeConnectionsCount[node].put(adjCom, nodeCountEdgesTo + 1);
}
if (to != adjCom) {
Float comEdgesto = to.connectionsWeight.get(adjCom);
if (comEdgesto == null) {
to.connectionsWeight.put(adjCom, e.weight);
} else {
to.connectionsWeight.put(adjCom, comEdgesto + e.weight);
}
Integer comCountEdgesto = to.connectionsCount.get(adjCom);
if (comCountEdgesto == null) {
to.connectionsCount.put(adjCom, 1);
} else {
to.connectionsCount.put(adjCom, comCountEdgesto + 1);
}
}
}
}
private void removeNodeFrom(int node, Community from) {
Community community = nodeCommunities[node];
for (ModEdge e : topology[node]) {
int neighbor = e.target;
////////
//Remove Node Connection to this community
Float edgesTo = nodeConnectionsWeight[neighbor].get(community);
Integer countEdgesTo = nodeConnectionsCount[neighbor].get(community);
if (countEdgesTo - 1 == 0) {
nodeConnectionsWeight[neighbor].remove(community);
nodeConnectionsCount[neighbor].remove(community);
} else {
nodeConnectionsWeight[neighbor].put(community, edgesTo - e.weight);
nodeConnectionsCount[neighbor].put(community, countEdgesTo - 1);
}
///////////////////
//Remove Adjacency Community's connection to this community
Modularity.Community adjCom = nodeCommunities[neighbor];
Float oEdgesto = adjCom.connectionsWeight.get(community);
Integer oCountEdgesto = adjCom.connectionsCount.get(community);
if (oCountEdgesto - 1 == 0) {
adjCom.connectionsWeight.remove(community);
adjCom.connectionsCount.remove(community);
} else {
adjCom.connectionsWeight.put(community, oEdgesto - e.weight);
adjCom.connectionsCount.put(community, oCountEdgesto - 1);
}
if (node == neighbor) {
continue;
}
if (adjCom != community) {
Float comEdgesto = community.connectionsWeight.get(adjCom);
Integer comCountEdgesto = community.connectionsCount.get(adjCom);
if (comCountEdgesto - 1 == 0) {
community.connectionsWeight.remove(adjCom);
community.connectionsCount.remove(adjCom);
} else {
community.connectionsWeight.put(adjCom, comEdgesto - e.weight);
community.connectionsCount.put(adjCom, comCountEdgesto - 1);
}
}
Float nodeEgesTo = nodeConnectionsWeight[node].get(adjCom);
Integer nodeCountEgesTo = nodeConnectionsCount[node].get(adjCom);
if (nodeCountEgesTo - 1 == 0) {
nodeConnectionsWeight[node].remove(adjCom);
nodeConnectionsCount[node].remove(adjCom);
} else {
nodeConnectionsWeight[node].put(adjCom, nodeEgesTo - e.weight);
nodeConnectionsCount[node].put(adjCom, nodeCountEgesTo - 1);
}
}
from.remove(new Integer(node));
}
private void moveNodeTo(int node, Community to) {
Community from = nodeCommunities[node];
removeNodeFrom(node, from);
addNodeTo(node, to);
}
private void zoomOut() {
int M = communities.size();
LinkedList<ModEdge>[] newTopology = new LinkedList[M];
int index = 0;
nodeCommunities = new Community[M];
nodeConnectionsWeight = new HashMap[M];
nodeConnectionsCount = new HashMap[M];
HashMap<Integer, Community> newInvMap = new HashMap<Integer, Community>();
for (int i = 0; i < communities.size(); i++) {//Community com : mCommunities) {
Community com = communities.get(i);
nodeConnectionsWeight[index] = new HashMap<Community, Float>();
nodeConnectionsCount[index] = new HashMap<Community, Integer>();
newTopology[index] = new LinkedList<ModEdge>();
nodeCommunities[index] = new Community(com);
Set<Community> iter = com.connectionsWeight.keySet();
double weightSum = 0;
Community hidden = new Community(structure);
for (Integer nodeInt : com.nodes) {
Community oldHidden = invMap.get(nodeInt);
hidden.nodes.addAll(oldHidden.nodes);
}
newInvMap.put(index, hidden);
for (Modularity.Community adjCom : iter) {
int target = communities.indexOf(adjCom);
float weight = com.connectionsWeight.get(adjCom);
if (target == index) {
weightSum += 2. * weight;
} else {
weightSum += weight;
}
ModEdge e = new ModEdge(index, target, weight);
newTopology[index].add(e);
}
weights[index] = weightSum;
nodeCommunities[index].seed(index);
index++;
}
communities.clear();
for (int i = 0; i < M; i++) {
Community com = nodeCommunities[i];
communities.add(com);
for (ModEdge e : newTopology[i]) {
nodeConnectionsWeight[i].put(nodeCommunities[e.target], e.weight);
nodeConnectionsCount[i].put(nodeCommunities[e.target], 1);
com.connectionsWeight.put(nodeCommunities[e.target], e.weight);
com.connectionsCount.put(nodeCommunities[e.target], 1);
}
}
N = M;
topology = newTopology;
invMap = newInvMap;
}
}
class Community {
double weightSum;
CommunityStructure structure;
LinkedList<Integer> nodes;
HashMap<Modularity.Community, Float> connectionsWeight;
HashMap<Modularity.Community, Integer> connectionsCount;
public int size() {
return nodes.size();
}
public Community(Modularity.Community com) {
structure = com.structure;
connectionsWeight = new HashMap<Modularity.Community, Float>();
connectionsCount = new HashMap<Modularity.Community, Integer>();
nodes = new LinkedList<Integer>();
//mHidden = pCom.mHidden;
}
public Community(CommunityStructure structure) {
this.structure = structure;
connectionsWeight = new HashMap<Modularity.Community, Float>();
connectionsCount = new HashMap<Modularity.Community, Integer>();
nodes = new LinkedList<Integer>();
}
public void seed(int node) {
nodes.add(node);
weightSum += structure.weights[node];
}
public boolean add(int node) {
nodes.addLast(new Integer(node));
weightSum += structure.weights[node];
return true;
}
public boolean remove(int node) {
boolean result = nodes.remove(new Integer(node));
weightSum -= structure.weights[node];
if (nodes.size() == 0) {
structure.communities.remove(this);
}
return result;
}
}
@Override
public void execute(GraphModel graphModel, AttributeModel attributeModel) {
Graph hgraph = graphModel.getUndirectedGraphVisible();
execute(hgraph, attributeModel);
}
public void execute(Graph hgraph, AttributeModel attributeModel) {
isCanceled = false;
hgraph.readLock();
structure = new Modularity.CommunityStructure(hgraph);
int[] comStructure = new int[hgraph.getNodeCount()];
HashMap<String, Double> computedModularityMetrics = computeModularity(hgraph, structure, comStructure, resolution, isRandomized, useWeight);
modularity = computedModularityMetrics.get("modularity");
modularityResolution = computedModularityMetrics.get("modularityResolution");
saveValues(comStructure, hgraph, attributeModel, structure);
hgraph.readUnlock();
}
protected HashMap<String, Double> computeModularity(Graph hgraph, CommunityStructure theStructure, int[] comStructure,
double currentResolution, boolean randomized, boolean weighted) {
isCanceled = false;
Progress.start(progress);
Random rand = new Random();
double totalWeight = theStructure.graphWeightSum;
double[] nodeDegrees = theStructure.weights.clone();
HashMap<String, Double> results = new HashMap<String, Double>();
if (isCanceled) {
hgraph.readUnlockAll();
return results;
}
boolean someChange = true;
while (someChange) {
someChange = false;
boolean localChange = true;
while (localChange) {
localChange = false;
int start = 0;
if (randomized) {
start = Math.abs(rand.nextInt()) % theStructure.N;
}
int step = 0;
for (int i = start; step < theStructure.N; i = (i + 1) % theStructure.N) {
step++;
Community bestCommunity = updateBestCommunity(theStructure, i, currentResolution);
if ((theStructure.nodeCommunities[i] != bestCommunity) && (bestCommunity != null)) {
theStructure.moveNodeTo(i, bestCommunity);
localChange = true;
}
if (isCanceled) {
hgraph.readUnlockAll();
return results;
}
}
someChange = localChange || someChange;
if (isCanceled) {
hgraph.readUnlockAll();
return results;
}
}
if (someChange) {
theStructure.zoomOut();
}
}
fillComStructure(hgraph, theStructure, comStructure);
double[] degreeCount = fillDegreeCount(hgraph, theStructure, comStructure, nodeDegrees, weighted);
double computedModularity = finalQ(comStructure, degreeCount, hgraph, theStructure, totalWeight, 1., weighted);
double computedModularityResolution = finalQ(comStructure, degreeCount, hgraph, theStructure, totalWeight, currentResolution, weighted);
results.put("modularity", computedModularity);
results.put("modularityResolution", computedModularityResolution);
return results;
}
Community updateBestCommunity(CommunityStructure theStructure, int i, double currentResolution) {
double best = 0.;
Community bestCommunity = null;
Set<Community> iter = theStructure.nodeConnectionsWeight[i].keySet();
for (Community com : iter) {
double qValue = q(i, com, theStructure, currentResolution);
if (qValue > best) {
best = qValue;
bestCommunity = com;
}
}
return bestCommunity;
}
int[] fillComStructure(Graph hgraph, CommunityStructure theStructure, int[] comStructure) {
// int[] comStructure = new int[hgraph.getNodeCount()];
int count = 0;
for (Community com : theStructure.communities) {
for (Integer node : com.nodes) {
Community hidden = theStructure.invMap.get(node);
for (Integer nodeInt : hidden.nodes) {
comStructure[nodeInt] = count;
}
}
count++;
}
return comStructure;
}
double[] fillDegreeCount(Graph hgraph, CommunityStructure theStructure, int[] comStructure, double[] nodeDegrees, boolean weighted) {
double[] degreeCount = new double[theStructure.communities.size()];
for (Node node : hgraph.getNodes()) {
int index = theStructure.map.get(node);
if (weighted) {
degreeCount[comStructure[index]] += nodeDegrees[index];
} else {
degreeCount[comStructure[index]] += hgraph.getDegree(node);
}
}
return degreeCount;
}
private double finalQ(int[] struct, double[] degrees, Graph hgraph,
CommunityStructure theStructure, double totalWeight, double usedResolution, boolean weighted) {
double res = 0;
double[] internal = new double[degrees.length];
for (Node n : hgraph.getNodes()) {
int n_index = theStructure.map.get(n);
for (Node neighbor : hgraph.getNeighbors(n)) {
if (n == neighbor) {
continue;
}
int neigh_index = theStructure.map.get(neighbor);
if (struct[neigh_index] == struct[n_index]) {
if (weighted) {
internal[struct[neigh_index]] += hgraph.getEdge(n, neighbor).getWeight();
} else {
internal[struct[neigh_index]]++;
}
}
}
}
for (int i = 0; i < degrees.length; i++) {
internal[i] /= 2.0;
res += usedResolution * (internal[i] / totalWeight) - Math.pow(degrees[i] / (2 * totalWeight), 2);//HERE
}
return res;
}
private void saveValues(int[] struct, Graph hgraph, AttributeModel attributeModel, CommunityStructure theStructure) {
Table nodeTable = attributeModel.getNodeTable();
Column modCol = nodeTable.getColumn(MODULARITY_CLASS);
if (modCol == null) {
modCol = nodeTable.addColumn(MODULARITY_CLASS, "Modularity Class", Integer.class, new Integer(0));
}
for (Node n : hgraph.getNodes()) {
int n_index = theStructure.map.get(n);;
n.setAttribute(modCol, struct[n_index]);
}
}
public double getModularity() {
return modularity;
}
@Override
public String getReport() {
//Distribution series
Map<Integer, Integer> sizeDist = new HashMap<Integer, Integer>();
for (Node n : structure.graph.getNodes()) {
Integer v = (Integer) n.getAttribute(MODULARITY_CLASS);
if (!sizeDist.containsKey(v)) {
sizeDist.put(v, 0);
}
sizeDist.put(v, sizeDist.get(v) + 1);
}
XYSeries dSeries = ChartUtils.createXYSeries(sizeDist, "Size Distribution");
XYSeriesCollection dataset1 = new XYSeriesCollection();
dataset1.addSeries(dSeries);
JFreeChart chart = ChartFactory.createXYLineChart(
"Size Distribution",
"Modularity Class",
"Size (number of nodes)",
dataset1,
PlotOrientation.VERTICAL,
true,
false,
false);
chart.removeLegend();
ChartUtils.decorateChart(chart);
ChartUtils.scaleChart(chart, dSeries, false);
String imageFile = ChartUtils.renderChart(chart, "communities-size-distribution.png");
NumberFormat f = new DecimalFormat("#0.000");
String report = "<HTML> <BODY> <h1>Modularity Report </h1> "
+ "<hr>"
+ "<h2> Parameters: </h2>"
+ "Randomize: " + (isRandomized ? "On" : "Off") + "<br>"
+ "Use edge weights: " + (useWeight ? "On" : "Off") + "<br>"
+ "Resolution: " + (resolution) + "<br>"
+ "<br> <h2> Results: </h2>"
+ "Modularity: " + f.format(modularity) + "<br>"
+ "Modularity with resolution: " + f.format(modularityResolution) + "<br>"
+ "Number of Communities: " + structure.communities.size()
+ "<br /><br />" + imageFile
+ "<br /><br />" + "<h2> Algorithm: </h2>"
+ "Vincent D Blondel, Jean-Loup Guillaume, Renaud Lambiotte, Etienne Lefebvre, <i>Fast unfolding of communities in large networks</i>, in Journal of Statistical Mechanics: Theory and Experiment 2008 (10), P1000<br />"
+ "<br /><br />" + "<h2> Resolution: </h2>"
+ "R. Lambiotte, J.-C. Delvenne, M. Barahona <i>Laplacian Dynamics and Multiscale Modular Structure in Networks 2009<br />"
+ "</BODY> </HTML>";
return report;
}
private double q(int node, Community community, CommunityStructure theStructure, double currentResolution) {
Float edgesToFloat = theStructure.nodeConnectionsWeight[node].get(community);
double edgesTo = 0;
if (edgesToFloat != null) {
edgesTo = edgesToFloat.doubleValue();
}
double weightSum = community.weightSum;
double nodeWeight = theStructure.weights[node];
double qValue = currentResolution * edgesTo - (nodeWeight * weightSum) / (2.0 * theStructure.graphWeightSum);
if ((theStructure.nodeCommunities[node] == community) && (theStructure.nodeCommunities[node].size() > 1)) {
qValue = currentResolution * edgesTo - (nodeWeight * (weightSum - nodeWeight)) / (2.0 * theStructure.graphWeightSum);
}
if ((theStructure.nodeCommunities[node] == community) && (theStructure.nodeCommunities[node].size() == 1)) {
qValue = 0.;
}
return qValue;
}
}