1 /*
2 * Licensed to the Hipparchus project 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 Hipparchus project 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 * https://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 package org.hipparchus.optim.nonlinear.vector.constrained;
18
19
20 import org.hipparchus.linear.Array2DRowRealMatrix;
21 import org.hipparchus.linear.ArrayRealVector;
22 import org.hipparchus.linear.RealMatrix;
23 import org.hipparchus.linear.RealVector;
24 import org.hipparchus.optim.OptimizationData;
25 /** A set of linear equality constraints given as Ax = b.
26 * @since 3.1
27 */
28 public class LinearEqualityConstraint extends EqualityConstraint implements OptimizationData {
29
30 /** Matrix of linear weights. */
31 private final RealMatrix a;
32
33 /**
34 * Construct a set of linear equality constraints ax = b. Represents
35 * equations a[i].x = b[i], for each row of a.
36 *
37 * @param a the matrix of linear weights
38 * @param b the vector of constants
39 */
40 public LinearEqualityConstraint(final RealMatrix a, final RealVector b) {
41 super(b);
42 this.a = a;
43 }
44
45 /**
46 * Construct a set of linear equality constraints ax = b. Represents
47 * equations a[i].x = b[i], for each row of a.
48 *
49 * @param a the matrix of linear weights
50 * @param b the vector of constants
51 */
52 public LinearEqualityConstraint(final double[][] a, final double[] b) {
53 this(new Array2DRowRealMatrix(a), new ArrayRealVector(b));
54 }
55
56 /** Get the matrix of linear weights.
57 * @return matrix of linear weights
58 */
59 public RealMatrix getA() {
60 return a;
61 }
62
63 @Override
64 public int dim() {
65 return a.getColumnDimension();
66 }
67
68 @Override
69 public RealVector value(final RealVector x) {
70 return a.operate(x);
71 }
72
73 @Override
74 public RealMatrix jacobian(final RealVector x) {
75 return a.copy();
76 }
77
78 }