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    package org.apache.commons.math3.optim;
018    
019    /**
020     * Base class for all convergence checker implementations.
021     *
022     * @param <PAIR> Type of (point, value) pair.
023     *
024     * @version $Id: AbstractConvergenceChecker.java 1370215 2012-08-07 12:38:59Z sebb $
025     * @since 3.0
026     */
027    public abstract class AbstractConvergenceChecker<PAIR>
028        implements ConvergenceChecker<PAIR> {
029        /**
030         * Relative tolerance threshold.
031         */
032        private final double relativeThreshold;
033        /**
034         * Absolute tolerance threshold.
035         */
036        private final double absoluteThreshold;
037    
038        /**
039         * Build an instance with a specified thresholds.
040         *
041         * @param relativeThreshold relative tolerance threshold
042         * @param absoluteThreshold absolute tolerance threshold
043         */
044        public AbstractConvergenceChecker(final double relativeThreshold,
045                                          final double absoluteThreshold) {
046            this.relativeThreshold = relativeThreshold;
047            this.absoluteThreshold = absoluteThreshold;
048        }
049    
050        /**
051         * @return the relative threshold.
052         */
053        public double getRelativeThreshold() {
054            return relativeThreshold;
055        }
056    
057        /**
058         * @return the absolute threshold.
059         */
060        public double getAbsoluteThreshold() {
061            return absoluteThreshold;
062        }
063    
064        /**
065         * {@inheritDoc}
066         */
067        public abstract boolean converged(int iteration,
068                                          PAIR previous,
069                                          PAIR current);
070    }