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 */
017package org.apache.commons.math4.optim;
018
019/**
020 * Base class for all convergence checker implementations.
021 *
022 * @param <PAIR> Type of (point, value) pair.
023 *
024 * @since 3.0
025 */
026public abstract class AbstractConvergenceChecker<PAIR>
027    implements ConvergenceChecker<PAIR> {
028    /**
029     * Relative tolerance threshold.
030     */
031    private final double relativeThreshold;
032    /**
033     * Absolute tolerance threshold.
034     */
035    private final double absoluteThreshold;
036
037    /**
038     * Build an instance with a specified thresholds.
039     *
040     * @param relativeThreshold relative tolerance threshold
041     * @param absoluteThreshold absolute tolerance threshold
042     */
043    public AbstractConvergenceChecker(final double relativeThreshold,
044                                      final double absoluteThreshold) {
045        this.relativeThreshold = relativeThreshold;
046        this.absoluteThreshold = absoluteThreshold;
047    }
048
049    /**
050     * @return the relative threshold.
051     */
052    public double getRelativeThreshold() {
053        return relativeThreshold;
054    }
055
056    /**
057     * @return the absolute threshold.
058     */
059    public double getAbsoluteThreshold() {
060        return absoluteThreshold;
061    }
062
063    /**
064     * {@inheritDoc}
065     */
066    @Override
067    public abstract boolean converged(int iteration,
068                                      PAIR previous,
069                                      PAIR current);
070}