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SSJ is a Java library for stochastic simulation, developed under the direction of Pierre L'Ecuyer, in the Département d'Informatique et de Recherche Opérationnelle (DIRO), at the Université de Montréal. It provides facilities for generating uniform and nonuniform random variates, computing different measures related to probability distributions, performing goodness-of-fit tests, applying quasi-Monte Carlo methods, collecting (elementary) statistics, and programming discrete-event simulations with both events and processes.

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/*
 * Class:        IIDMultivariateGen
 * Description:  vector of independent identically distributed random variables
 * Environment:  Java
 * Software:     SSJ 
 * Copyright (C) 2001  Pierre L'Ecuyer and Université de Montréal
 * Organization: DIRO, Université de Montréal
 * @author       David Munger
 * @since        January 2011

 * SSJ is free software: you can redistribute it and/or modify it under
 * the terms of the GNU General Public License (GPL) as published by the
 * Free Software Foundation, either version 3 of the License, or
 * any later version.

 * SSJ 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.

 * A copy of the GNU General Public License is available at
   GPL licence site.
 */

package umontreal.iro.lecuyer.randvarmulti;

import umontreal.iro.lecuyer.randvar.RandomVariateGen;


/**
 * Extends {@link RandomMultivariateGen} for a vector of independent identically distributed
 * (i.i.d.) random variables.
 * 
 */
public class IIDMultivariateGen extends RandomMultivariateGen {


   /**
    * Constructs a generator for a d-dimensional vector of i.i.d. variates
    * with a common one-dimensional generator gen1.
    * 
    * @param gen1 the one-dimensional generator
    * 
    *    @param d dimension of the vector (number of i.i.d. variates).
    * 
    */
   public IIDMultivariateGen (RandomVariateGen gen1, int d)  {
      setGen1 (gen1);
      this.stream = gen1.getStream();
      dimension = d;
   } 


   /**
    * Changes the dimension of the vector to d.
    * 
    */
   public void setDimension (int d)  {
      dimension = d;
   } 


   /**
    * Generates a vector of i.i.d. variates.
    * 
    */
   public void nextPoint (double[] p)  {
      if (p.length != dimension)
         throw new IllegalArgumentException(String.format(
            "p's dimension (%d) does not mach dimension (%d)", p.length, dimension));

      for (int i = 0; i < dimension; i++)
         p[i] = gen1.nextDouble();
   } 


   /**
    * Sets the common one-dimensional generator to gen1.
    * 
    */
   public void setGen1 (RandomVariateGen gen1) {
      if (gen1 == null)
         throw new NullPointerException ("gen1 is null");
      this.gen1 = gen1;
   } 


   /**
    * Returns the common one-dimensional generator used in this class.
    * 
    */
   public RandomVariateGen getGen1() {
     return gen1;
   } 


   /**
    * Returns a string representation of the generator.
    * 
    */
   public String toString()  {
      return dimension + "-dimensional vector of i.i.d. " +
            gen1.getDistribution().toString();
   }
   

}