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 }