    001    /*
    002     * Licensed to the Apache Software Foundation (ASF) under one or more
    003     * contributor license agreements.  See the NOTICE file distributed with
    004     * this work for additional information regarding copyright ownership.
    005     * The ASF licenses this file to You under the Apache License, Version 2.0
    006     * (the "License"); you may not use this file except in compliance with
    007     * the License.  You may obtain a copy of the License at
    008     *
    009     *      http://www.apache.org/licenses/LICENSE-2.0
    010     *
    011     * Unless required by applicable law or agreed to in writing, software
    012     * distributed under the License is distributed on an "AS IS" BASIS,
    013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    014     * See the License for the specific language governing permissions and
    015     * limitations under the License.
    016     */
    017
    018    package org.apache.commons.math.optimization;
    019
    020    import java.io.Serializable;
    021
    022
    023    /**
    024     * This class holds a point and the value of an objective function at this point.
    025     * <p>This is a simple immutable container.</p>
    026     * @see VectorialPointValuePair
    027     * @see org.apache.commons.math.analysis.MultivariateRealFunction
    028     * @version $Revision: 980981 $ $Date: 2010-07-31 00:03:04 +0200 (sam. 31 juil. 2010) $
    029     * @since 2.0
    030     */
    031    public class RealPointValuePair implements Serializable {
    032        /** Serializable version identifier. */
    033        private static final long serialVersionUID = 1003888396256744753L;
    034
    035        /** Point coordinates. */
    036        private final double[] point;
    037
    038        /** Value of the objective function at the point. */
    039        private final double value;
    040
    041        /** Build a point/objective function value pair.
    042         * @param point point coordinates (the built instance will store
    043         * a copy of the array, not the array passed as argument)
    044         * @param value value of an objective function at the point
    045         */
    046        public RealPointValuePair(final double[] point, final double value) {
    047            this.point = (point == null) ? null : point.clone();
    048            this.value  = value;
    049        }
    050
    051        /** Build a point/objective function value pair.
    052         * @param point point coordinates (the built instance will store
    053         * a copy of the array, not the array passed as argument)
    054         * @param value value of an objective function at the point
    055         * @param copyArray if true, the input array will be copied, otherwise
    056         * it will be referenced
    057         */
    058        public RealPointValuePair(final double[] point, final double value,
    059                                  final boolean copyArray) {
    060            this.point = copyArray ?
    061                         ((point == null) ? null : point.clone()) :
    062                         point;
    063            this.value  = value;
    064        }
    065
    066        /** Get the point.
    067         * @return a copy of the stored point
    068         */
    069        public double[] getPoint() {
    070            return (point == null) ? null : point.clone();
    071        }
    072
    073        /** Get a reference to the point.
    074         * <p>This method is provided as a convenience to avoid copying
    075         * the array, the elements of the array should <em>not</em> be modified.</p>
    076         * @return a reference to the internal array storing the point
    077         */
    078        public double[] getPointRef() {
    079            return point;
    080        }
    081
    082        /** Get the value of the objective function.
    083         * @return the stored value of the objective function
    084         */
    085        public double getValue() {
    086            return value;
    087        }
    088    }