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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
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 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
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package org.apache.commons.math3.util;

import java.io.Serializable;

import org.apache.commons.math3.exception.MathIllegalArgumentException;


A mid point strategy based on the average of begin and end indices.
Since:3.4
/** * A mid point strategy based on the average of begin and end indices. * @since 3.4 */
public class CentralPivotingStrategy implements PivotingStrategyInterface, Serializable {
Serializable UID.
/** Serializable UID. */
private static final long serialVersionUID = 20140713L;
{@inheritDoc} This in particular picks a average of begin and end indices
Throws:
Returns:The index corresponding to a simple average of the first and the last element indices of the array slice
/** * {@inheritDoc} * This in particular picks a average of begin and end indices * @return The index corresponding to a simple average of * the first and the last element indices of the array slice * @throws MathIllegalArgumentException when indices exceeds range */
public int pivotIndex(final double[] work, final int begin, final int end) throws MathIllegalArgumentException { MathArrays.verifyValues(work, begin, end-begin); return begin + (end - begin)/2; } }