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diff --git a/src/main/java/org/apache/commons/math/genetics/ElitisticListPopulation.java b/src/main/java/org/apache/commons/math/genetics/ElitisticListPopulation.java
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+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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 org.apache.commons.math.genetics;
+
+import java.util.Collections;
+import java.util.List;
+
+import org.apache.commons.math.util.FastMath;
+
+/**
+ * Population of chromosomes which uses elitism (certain percentace of the best
+ * chromosomes is directly copied to the next generation).
+ *
+ * @version $Revision: 990655 $ $Date: 2010-08-29 23:49:40 +0200 (dim. 29 août 2010) $
+ * @since 2.0
+ */
+public class ElitisticListPopulation extends ListPopulation {
+
+    /** percentage of chromosomes copied to the next generation */
+    private double elitismRate = 0.9;
+
+    /**
+     * Creates a new ElitisticListPopulation instance.
+     *
+     * @param chromosomes
+     *            list of chromosomes in the population
+     * @param populationLimit
+     *            maximal size of the population
+     * @param elitismRate
+     *            how many best chromosomes will be directly transferred to the
+     *            next generation [in %]
+     */
+    public ElitisticListPopulation(List<Chromosome> chromosomes, int populationLimit, double elitismRate) {
+        super(chromosomes, populationLimit);
+        this.elitismRate = elitismRate;
+    }
+
+    /**
+     * Creates a new ListPopulation instance and initializes its inner
+     * chromosome list.
+     *
+     * @param populationLimit maximal size of the population
+     * @param elitismRate
+     *            how many best chromosomes will be directly transferred to the
+     *            next generation [in %]
+     */
+    public ElitisticListPopulation(int populationLimit, double elitismRate) {
+        super(populationLimit);
+        this.elitismRate = elitismRate;
+    }
+
+    /**
+     * Start the population for the next generation. The
+     * <code>{@link #elitismRate}<code> percents of the best
+     * chromosomes are directly copied to the next generation.
+     *
+     * @return the beginnings of the next generation.
+     */
+    public Population nextGeneration() {
+        // initialize a new generation with the same parameters
+        ElitisticListPopulation nextGeneration = new ElitisticListPopulation(this.getPopulationLimit(), this.getElitismRate());
+
+        List<Chromosome> oldChromosomes = this.getChromosomes();
+        Collections.sort(oldChromosomes);
+
+        // index of the last "not good enough" chromosome
+        int boundIndex = (int) FastMath.ceil((1.0 - this.getElitismRate()) * oldChromosomes.size());
+        for (int i=boundIndex; i<oldChromosomes.size(); i++) {
+            nextGeneration.addChromosome(oldChromosomes.get(i));
+        }
+        return nextGeneration;
+    }
+
+    /**
+     * Sets the elitism rate, i.e. how many best chromosomes will be directly
+     * transferred to the next generation [in %].
+     *
+     * @param elitismRate
+     *            how many best chromosomes will be directly transferred to the
+     *            next generation [in %]
+     */
+    public void setElitismRate(double elitismRate) {
+        if (elitismRate < 0 || elitismRate > 1)
+            throw new IllegalArgumentException("Elitism rate has to be in [0,1]");
+        this.elitismRate = elitismRate;
+    }
+
+    /**
+     * Access the elitism rate.
+     * @return the elitism rate
+     */
+    public double getElitismRate() {
+        return this.elitismRate;
+    }
+
+}