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.nonlinear.scalar;
18
19 import org.apache.commons.math4.legacy.exception.NotStrictlyPositiveException;
20 import org.apache.commons.math4.legacy.optim.Tolerance;
21
22 /**
23 * Tolerances for line search.
24 *
25 * @since 4.0
26 */
27 public class LineSearchTolerance extends Tolerance {
28 /** Range. */
29 private final double initialBracketingRange;
30
31 /**
32 * @param relative Relative tolerance.
33 * @param absolute Absolute tolerance.
34 * @param range Extent of the initial interval used to find an interval
35 * that brackets the optimum.
36 * If the optimized function varies a lot in the vicinity of the optimum,
37 * it may be necessary to provide a value lower than the distance between
38 * successive local minima.
39 */
40 public LineSearchTolerance(double relative,
41 double absolute,
42 double range) {
43 super(relative, absolute);
44
45 if (range <= 0) {
46 throw new NotStrictlyPositiveException(range);
47 }
48
49 initialBracketingRange = range;
50 }
51
52 /** @return the initial bracketing range. */
53 public double getInitialBracketingRange() {
54 return initialBracketingRange;
55 }
56 }