org.jgrapht.experimental.UniformRandomGraphGenerator Maven / Gradle / Ivy
/* ==========================================
* JGraphT : a free Java graph-theory library
* ==========================================
*
* Project Info: http://jgrapht.sourceforge.net/
* Project Creator: Barak Naveh (http://sourceforge.net/users/barak_naveh)
*
* (C) Copyright 2003-2008, by Barak Naveh and Contributors.
*
* This program and the accompanying materials are dual-licensed under
* either
*
* (a) the terms of the GNU Lesser General Public License version 2.1
* as published by the Free Software Foundation, or (at your option) any
* later version.
*
* or (per the licensee's choosing)
*
* (b) the terms of the Eclipse Public License v1.0 as published by
* the Eclipse Foundation.
*/
/* -------------------
* UniformRandomGraphGenerator.java
* -------------------
* (C) Copyright 2003-2008, by Michael Behrisch and Contributors.
*
* Original Author: Michael Behrisch
* Contributor(s): -
*
* $Id$
*
* Changes
* -------
* 13-Sep-2004 : Initial revision (MB);
*
*/
// package org.jgrapht.generate;
package org.jgrapht.experimental;
import java.util.*;
import org.jgrapht.*;
import org.jgrapht.generate.*;
/**
* UniformRandomGraphGenerator generates a uniform random graph
* of any size. A uniform random graph contains edges chosen independently
* uniformly at random from the set of all possible edges.
*
* @author Michael Behrisch
* @since Sep 13, 2004
*/
public class UniformRandomGraphGenerator
implements GraphGenerator
{
private final int numEdges;
private final int numVertices;
/**
* Construct a new UniformRandomGraphGenerator.
*
* @param numVertices number of vertices to be generated
* @param numEdges number of edges to be generated
*
* @throws IllegalArgumentException
*/
public UniformRandomGraphGenerator(int numVertices, int numEdges)
{
if (numVertices < 0) {
throw new IllegalArgumentException("must be non-negative");
}
if ((numEdges < 0)
|| (numEdges > (numVertices * (numVertices - 1) / 2)))
{
throw new IllegalArgumentException("illegal number of edges");
}
this.numVertices = numVertices;
this.numEdges = numEdges;
}
/**
* @see GraphGenerator#generateGraph
*/
@Override public void generateGraph(
Graph target,
VertexFactory vertexFactory,
Map resultMap)
{
Object [] vertices =
RandomGraphHelper.addVertices(
target,
vertexFactory,
numVertices);
RandomGraphHelper.addEdges(
target,
Arrays.asList(vertices),
Arrays.asList(vertices),
numEdges);
}
}
// End UniformRandomGraphGenerator.java