UniformIntGen.java

/*
 * Class:        UniformIntGen
 * Description:  random variate generator for the uniform distribution over integers
 * Environment:  Java
 * Software:     SSJ 
 * Copyright (C) 2001  Pierre L'Ecuyer and Universite de Montreal
 * Organization: DIRO, Universite de Montreal
 * @author       
 * @since
 *
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */
package umontreal.ssj.randvar;
 
import umontreal.ssj.rng.*;
import umontreal.ssj.probdist.*;

public class UniformIntGen extends RandomVariateGenInt {
   protected int left; // the left limit of the interval
   protected int right; // the right limit of the interval

   public UniformIntGen(RandomStream s, int i, int j) {
      super(s, new UniformIntDist(i, j));
      setParams(i, j);
   }

   public UniformIntGen(RandomStream s, UniformIntDist dist) {
      super(s, dist);
      if (dist != null)
         setParams(dist.getI(), dist.getJ());
   }

   public static int nextInt(RandomStream s, int i, int j) {
      return UniformIntDist.inverseF(i, j, s.nextDouble());
   }

   public int getI() {
      return left;
   }

   public int getJ() {
      return right;
   }
 
   protected void setParams(int i, int j) {
      if (j < i)
         throw new IllegalArgumentException("j < i");
      left = i;
      right = j;
   }
}