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.math3.optimization;
019
020 import org.apache.commons.math3.util.Precision;
021
022 /**
023 * Base class for all convergence checker implementations.
024 *
025 * @param <PAIR> Type of (point, value) pair.
026 *
027 * @version $Id: AbstractConvergenceChecker.java 1422230 2012-12-15 12:11:13Z erans $
028 * @deprecated As of 3.1 (to be removed in 4.0).
029 * @since 3.0
030 */
031 @Deprecated
032 public abstract class AbstractConvergenceChecker<PAIR>
033 implements ConvergenceChecker<PAIR> {
034 /**
035 * Default relative threshold.
036 * @deprecated in 3.1 (to be removed in 4.0) because this value is too small
037 * to be useful as a default (cf. MATH-798).
038 */
039 @Deprecated
040 private static final double DEFAULT_RELATIVE_THRESHOLD = 100 * Precision.EPSILON;
041 /**
042 * Default absolute threshold.
043 * @deprecated in 3.1 (to be removed in 4.0) because this value is too small
044 * to be useful as a default (cf. MATH-798).
045 */
046 @Deprecated
047 private static final double DEFAULT_ABSOLUTE_THRESHOLD = 100 * Precision.SAFE_MIN;
048 /**
049 * Relative tolerance threshold.
050 */
051 private final double relativeThreshold;
052 /**
053 * Absolute tolerance threshold.
054 */
055 private final double absoluteThreshold;
056
057 /**
058 * Build an instance with default thresholds.
059 * @deprecated in 3.1 (to be removed in 4.0). Convergence thresholds are
060 * problem-dependent. As this class is intended for users who want to set
061 * their own convergence criterion instead of relying on an algorithm's
062 * default procedure, they should also set the thresholds appropriately
063 * (cf. MATH-798).
064 */
065 @Deprecated
066 public AbstractConvergenceChecker() {
067 this.relativeThreshold = DEFAULT_RELATIVE_THRESHOLD;
068 this.absoluteThreshold = DEFAULT_ABSOLUTE_THRESHOLD;
069 }
070
071 /**
072 * Build an instance with a specified thresholds.
073 *
074 * @param relativeThreshold relative tolerance threshold
075 * @param absoluteThreshold absolute tolerance threshold
076 */
077 public AbstractConvergenceChecker(final double relativeThreshold,
078 final double absoluteThreshold) {
079 this.relativeThreshold = relativeThreshold;
080 this.absoluteThreshold = absoluteThreshold;
081 }
082
083 /**
084 * @return the relative threshold.
085 */
086 public double getRelativeThreshold() {
087 return relativeThreshold;
088 }
089
090 /**
091 * @return the absolute threshold.
092 */
093 public double getAbsoluteThreshold() {
094 return absoluteThreshold;
095 }
096
097 /**
098 * {@inheritDoc}
099 */
100 public abstract boolean converged(int iteration,
101 PAIR previous,
102 PAIR current);
103 }