1/*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements.  See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License.  You may obtain a copy of the License at
8 *
9 *      http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17
18package org.apache.commons.math.optimization;
19
20import java.io.Serializable;
21
22
23/**
24 * This class holds a point and the value of an objective function at this point.
25 * <p>This is a simple immutable container.</p>
26 * @see VectorialPointValuePair
27 * @see org.apache.commons.math.analysis.MultivariateRealFunction
28 * @version $Revision: 980981 $ $Date: 2010-07-31 00:03:04 +0200 (sam. 31 juil. 2010) $
29 * @since 2.0
30 */
31public class RealPointValuePair implements Serializable {
32    /** Serializable version identifier. */
33    private static final long serialVersionUID = 1003888396256744753L;
34
35    /** Point coordinates. */
36    private final double[] point;
37
38    /** Value of the objective function at the point. */
39    private final double value;
40
41    /** Build a point/objective function value pair.
42     * @param point point coordinates (the built instance will store
43     * a copy of the array, not the array passed as argument)
44     * @param value value of an objective function at the point
45     */
46    public RealPointValuePair(final double[] point, final double value) {
47        this.point = (point == null) ? null : point.clone();
48        this.value  = value;
49    }
50
51    /** Build a point/objective function value pair.
52     * @param point point coordinates (the built instance will store
53     * a copy of the array, not the array passed as argument)
54     * @param value value of an objective function at the point
55     * @param copyArray if true, the input array will be copied, otherwise
56     * it will be referenced
57     */
58    public RealPointValuePair(final double[] point, final double value,
59                              final boolean copyArray) {
60        this.point = copyArray ?
61                     ((point == null) ? null : point.clone()) :
62                     point;
63        this.value  = value;
64    }
65
66    /** Get the point.
67     * @return a copy of the stored point
68     */
69    public double[] getPoint() {
70        return (point == null) ? null : point.clone();
71    }
72
73    /** Get a reference to the point.
74     * <p>This method is provided as a convenience to avoid copying
75     * the array, the elements of the array should <em>not</em> be modified.</p>
76     * @return a reference to the internal array storing the point
77     */
78    public double[] getPointRef() {
79        return point;
80    }
81
82    /** Get the value of the objective function.
83     * @return the stored value of the objective function
84     */
85    public double getValue() {
86        return value;
87    }
88}
89