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.univariate;
018    
019    import org.apache.commons.math3.optim.OptimizationData;
020    import org.apache.commons.math3.exception.NumberIsTooLargeException;
021    import org.apache.commons.math3.exception.OutOfRangeException;
022    
023    /**
024     * Search interval and (optional) start value.
025     * <br/>
026     * Immutable class.
027     *
028     * @version $Id$
029     * @since 3.1
030     */
031    public class SearchInterval implements OptimizationData {
032        /** Lower bound. */
033        private final double lower;
034        /** Upper bound. */
035        private final double upper;
036        /** Start value. */
037        private final double start;
038    
039        /**
040         * @param lo Lower bound.
041         * @param hi Upper bound.
042         * @param init Start value.
043         * @throws NumberIsTooLargeException if {@code lo >= hi}.
044         * @throws OutOfRangeException if {@code init < lo} or {@code init > hi}.
045         */
046        public SearchInterval(double lo,
047                              double hi,
048                              double init) {
049            if (lo >= hi) {
050                throw new NumberIsTooLargeException(lo, hi, false);
051            }
052            if (init < lo ||
053                init > hi) {
054                throw new OutOfRangeException(init, lo, hi);
055            }
056    
057            lower = lo;
058            upper = hi;
059            start = init;
060        }
061    
062        /**
063         * @param lo Lower bound.
064         * @param hi Upper bound.
065         * @throws NumberIsTooLargeException if {@code lo >= hi}.
066         */
067        public SearchInterval(double lo,
068                              double hi) {
069            this(lo, hi, 0.5 * (lo + hi));
070        }
071    
072        /**
073         * Gets the lower bound.
074         *
075         * @return the lower bound.
076         */
077        public double getMin() {
078            return lower;
079        }
080        /**
081         * Gets the upper bound.
082         *
083         * @return the upper bound.
084         */
085        public double getMax() {
086            return upper;
087        }
088        /**
089         * Gets the start value.
090         *
091         * @return the start value.
092         */
093        public double getStartValue() {
094            return start;
095        }
096    }