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diff --git a/src/main/java/org/apache/commons/math/stat/clustering/EuclideanIntegerPoint.java b/src/main/java/org/apache/commons/math/stat/clustering/EuclideanIntegerPoint.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.stat.clustering;
+
+import java.io.Serializable;
+import java.util.Collection;
+
+import org.apache.commons.math.util.MathUtils;
+
+/**
+ * A simple implementation of {@link Clusterable} for points with integer coordinates.
+ * @version $Revision: 1042376 $ $Date: 2010-12-05 16:54:55 +0100 (dim. 05 déc. 2010) $
+ * @since 2.0
+ */
+public class EuclideanIntegerPoint implements Clusterable<EuclideanIntegerPoint>, Serializable {
+
+    /** Serializable version identifier. */
+    private static final long serialVersionUID = 3946024775784901369L;
+
+    /** Point coordinates. */
+    private final int[] point;
+
+    /**
+     * Build an instance wrapping an integer array.
+     * <p>The wrapped array is referenced, it is <em>not</em> copied.</p>
+     * @param point the n-dimensional point in integer space
+     */
+    public EuclideanIntegerPoint(final int[] point) {
+        this.point = point;
+    }
+
+    /**
+     * Get the n-dimensional point in integer space.
+     * @return a reference (not a copy!) to the wrapped array
+     */
+    public int[] getPoint() {
+        return point;
+    }
+
+    /** {@inheritDoc} */
+    public double distanceFrom(final EuclideanIntegerPoint p) {
+        return MathUtils.distance(point, p.getPoint());
+    }
+
+    /** {@inheritDoc} */
+    public EuclideanIntegerPoint centroidOf(final Collection<EuclideanIntegerPoint> points) {
+        int[] centroid = new int[getPoint().length];
+        for (EuclideanIntegerPoint p : points) {
+            for (int i = 0; i < centroid.length; i++) {
+                centroid[i] += p.getPoint()[i];
+            }
+        }
+        for (int i = 0; i < centroid.length; i++) {
+            centroid[i] /= points.size();
+        }
+        return new EuclideanIntegerPoint(centroid);
+    }
+
+    /** {@inheritDoc} */
+    @Override
+    public boolean equals(final Object other) {
+        if (!(other instanceof EuclideanIntegerPoint)) {
+            return false;
+        }
+        final int[] otherPoint = ((EuclideanIntegerPoint) other).getPoint();
+        if (point.length != otherPoint.length) {
+            return false;
+        }
+        for (int i = 0; i < point.length; i++) {
+            if (point[i] != otherPoint[i]) {
+                return false;
+            }
+        }
+        return true;
+    }
+
+    /** {@inheritDoc} */
+    @Override
+    public int hashCode() {
+        int hashCode = 0;
+        for (Integer i : point) {
+            hashCode += i.hashCode() * 13 + 7;
+        }
+        return hashCode;
+    }
+
+    /**
+     * {@inheritDoc}
+     * @since 2.1
+     */
+    @Override
+    public String toString() {
+        final StringBuilder buff = new StringBuilder("(");
+        final int[] coordinates = getPoint();
+        for (int i = 0; i < coordinates.length; i++) {
+            buff.append(coordinates[i]);
+            if (i < coordinates.length - 1) {
+                buff.append(",");
+            }
+        }
+        buff.append(")");
+        return buff.toString();
+    }
+
+}