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.math.distribution;
018    
019    /**
020     * The Exponential Distribution.
021     *
022     * <p>
023     * References:
024     * <ul>
025     * <li><a href="http://mathworld.wolfram.com/ExponentialDistribution.html">
026     * Exponential Distribution</a></li>
027     * </ul>
028     * </p>
029     *
030     * @version $Revision: 920852 $ $Date: 2010-03-09 07:53:44 -0500 (Tue, 09 Mar 2010) $
031     */
032    public interface ExponentialDistribution extends ContinuousDistribution, HasDensity<Double> {
033        /**
034         * Modify the mean.
035         * @param mean the new mean.
036         * @deprecated as of v2.1
037         */
038        @Deprecated
039        void setMean(double mean);
040    
041        /**
042         * Access the mean.
043         * @return the mean.
044         */
045        double getMean();
046    
047        /**
048         * Return the probability density for a particular point.
049         * @param x  The point at which the density should be computed.
050         * @return  The pdf at point x.
051         */
052        double density(Double x);
053    }