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 package org.apache.commons.math4.legacy.optim;
18
19 import org.apache.commons.math4.legacy.exception.TooManyEvaluationsException;
20 import org.apache.commons.math4.legacy.exception.TooManyIterationsException;
21 import org.apache.commons.math4.legacy.core.IntegerSequence;
22
23 /**
24 * Base class for implementing optimization problems. It contains the boiler-plate code
25 * for counting the number of evaluations of the objective function and the number of
26 * iterations of the algorithm, and storing the convergence checker.
27 *
28 * @param <PAIR> Type of the point/value pair returned by the optimization algorithm.
29 * @since 3.3
30 */
31 public abstract class AbstractOptimizationProblem<PAIR>
32 implements OptimizationProblem<PAIR> {
33
34 /** Callback to use for the evaluation counter. */
35 private static final MaxEvalCallback MAX_EVAL_CALLBACK = new MaxEvalCallback();
36 /** Callback to use for the iteration counter. */
37 private static final MaxIterCallback MAX_ITER_CALLBACK = new MaxIterCallback();
38
39 /** max evaluations. */
40 private final int maxEvaluations;
41 /** max iterations. */
42 private final int maxIterations;
43 /** Convergence checker. */
44 private final ConvergenceChecker<PAIR> checker;
45
46 /**
47 * Create an {@link AbstractOptimizationProblem} from the given data.
48 *
49 * @param maxEvaluations the number of allowed model function evaluations.
50 * @param maxIterations the number of allowed iterations.
51 * @param checker the convergence checker.
52 */
53 protected AbstractOptimizationProblem(final int maxEvaluations,
54 final int maxIterations,
55 final ConvergenceChecker<PAIR> checker) {
56 this.maxEvaluations = maxEvaluations;
57 this.maxIterations = maxIterations;
58 this.checker = checker;
59 }
60
61 /** {@inheritDoc} */
62 @Override
63 public IntegerSequence.Incrementor getEvaluationCounter() {
64 return IntegerSequence.Incrementor.create()
65 .withMaximalCount(maxEvaluations)
66 .withCallback(MAX_EVAL_CALLBACK);
67 }
68
69 /** {@inheritDoc} */
70 @Override
71 public IntegerSequence.Incrementor getIterationCounter() {
72 return IntegerSequence.Incrementor.create()
73 .withMaximalCount(maxIterations)
74 .withCallback(MAX_ITER_CALLBACK);
75 }
76
77 /** {@inheritDoc} */
78 @Override
79 public ConvergenceChecker<PAIR> getConvergenceChecker() {
80 return checker;
81 }
82
83 /** Defines the action to perform when reaching the maximum number of evaluations. */
84 private static final class MaxEvalCallback
85 implements IntegerSequence.Incrementor.MaxCountExceededCallback {
86 /**
87 * {@inheritDoc}
88 *
89 * @throws TooManyEvaluationsException
90 */
91 @Override
92 public void trigger(int max) {
93 throw new TooManyEvaluationsException(max);
94 }
95 }
96
97 /** Defines the action to perform when reaching the maximum number of evaluations. */
98 private static final class MaxIterCallback
99 implements IntegerSequence.Incrementor.MaxCountExceededCallback {
100 /**
101 * {@inheritDoc}
102 *
103 * @throws TooManyIterationsException
104 */
105 @Override
106 public void trigger(int max) {
107 throw new TooManyIterationsException(max);
108 }
109 }
110 }