org.jgrapht.experimental.RandomGraphHelper 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.
*/
/* -------------------
* RandomGraphHelper.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.*;
/**
* 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 final class RandomGraphHelper
{
private static final Random randSingleton = new Random();
/**
* .
*/
private RandomGraphHelper()
{
}
/**
* @see org.jgrapht.generate.GraphGenerator#generateGraph
*/
@SuppressWarnings("unchecked")
public static void addEdges(
Graph target,
List sourceVertices,
List destVertices,
int numEdges)
{
int sourceSize = sourceVertices.size();
int destSize = destVertices.size();
for (int i = 0; i < numEdges; ++i) {
while (
target.addEdge(
sourceVertices.get(randSingleton.nextInt(
sourceSize)),
destVertices.get(randSingleton.nextInt(destSize)))
== null)
{
;
}
}
}
/**
* .
*
* @param target
* @param vertexFactory
* @param numVertices
*
* @return vertices
*/
@SuppressWarnings("unchecked")
public static Object [] addVertices(
Graph target,
VertexFactory vertexFactory,
int numVertices)
{
Object [] vertices = new Object[numVertices];
for (int i = 0; i < numVertices; ++i) {
vertices[i] = vertexFactory.createVertex();
target.addVertex(vertices[i]);
}
return vertices;
}
}
// End RandomGraphHelper.java