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.math.distribution;
019    
020    /**
021     * Normal (Gauss) Distribution.
022     *
023     * <p>
024     * References:</p><p>
025     * <ul>
026     * <li><a href="http://mathworld.wolfram.com/NormalDistribution.html">
027     * Normal Distribution</a></li>
028     * </ul>
029     * </p>
030     *
031     * @version $Revision: 693598 $ $Date: 2008-09-09 16:37:08 -0400 (Tue, 09 Sep 2008) $
032     */
033    public interface NormalDistribution extends ContinuousDistribution, HasDensity<Double> {
034        /**
035         * Access the mean.
036         * @return mean for this distribution
037         */
038        double getMean();
039        /**
040         * Modify the mean.
041         * @param mean for this distribution
042         */
043        void setMean(double mean);
044        /**
045         * Access the standard deviation.
046         * @return standard deviation for this distribution
047         */
048        double getStandardDeviation();
049        /**
050         * Modify the standard deviation.
051         * @param sd standard deviation for this distribution
052         */
053        void setStandardDeviation(double sd);
054    
055        /**
056         * Return the probability density for a particular point.
057         * @param x  The point at which the density should be computed.
058         * @return  The pdf at point x.
059         */
060        double density(Double x);
061    }