hyperexp.java

一个用于排队系统仿真的开源软件,有非常形象的图象仿真过程!

/**    
  * Copyright (C) 2006, Laboratorio di Valutazione delle Prestazioni - Politecnico di Milano

  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 of the License, or
  * (at your option) any later version.

  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.

  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  */
  
package jmt.engine.random;

import jmt.common.exception.IncorrectDistributionParameterException;
import jmt.engine.random.engine.RandomEngine;


/**
 *
 * This is the Hyper Exponential distribution (see the constructor
 * description for dettails).
 *
 * <br><br>Copyright (c) 2003
 * <br>Politecnico di Milano - dipartimento di Elettronica e Informazione
 * @author Fabrizio Frontera - [e-mail]
 */

public class HyperExp extends Distribution {


	protected Exponential expDistr;

	/**
	 * This is the constructor. It creates a new hyper exponential distribution which
	 * is constituted by N exponential "servers" chosen with probability alpha_i.
	 *
	 */
	public HyperExp() {
		engine = RandomEngine.makeDefault();
		expDistr = new Exponential();
	}


    //TODO: perch