/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.commons.math.distribution;

/**
 * Normal (Gauss) Distribution.
 *
 * <p>
 * References:
 * </p>
 * <p>
 * <ul>
 * <li><a href="http://mathworld.wolfram.com/NormalDistribution.html"> Normal
 * Distribution</a></li>
 * </ul>
 * </p>
 *
 * @version $Revision$ $Date$
 */
public interface NormalDistribution extends ContinuousDistribution, HasDensity<Double> {
	/**
	 * Access the mean.
	 * 
	 * @return mean for this distribution
	 */
	double getMean();

	/**
	 * Modify the mean.
	 * 
	 * @param mean
	 *            for this distribution
	 */
	void setMean(double mean);

	/**
	 * Access the standard deviation.
	 * 
	 * @return standard deviation for this distribution
	 */
	double getStandardDeviation();

	/**
	 * Modify the standard deviation.
	 * 
	 * @param sd
	 *            standard deviation for this distribution
	 */
	void setStandardDeviation(double sd);

	/**
	 * Return the probability density for a particular point.
	 * 
	 * @param x
	 *            The point at which the density should be computed.
	 * @return The pdf at point x.
	 */
	double density(Double x);
}
