Java tutorial
/* * 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.stat.descriptive; /** * Reporting interface for basic univariate statistics. * * @version $Revision: 811786 $ $Date: 2009-09-06 11:36:08 +0200 (dim. 06 sept. 2009) $ */ public interface StatisticalSummary { /** * Returns the <a href="http://www.xycoon.com/arithmetic_mean.htm"> * arithmetic mean </a> of the available values * @return The mean or Double.NaN if no values have been added. */ double getMean(); /** * Returns the variance of the available values. * @return The variance, Double.NaN if no values have been added * or 0.0 for a single value set. */ double getVariance(); /** * Returns the standard deviation of the available values. * @return The standard deviation, Double.NaN if no values have been added * or 0.0 for a single value set. */ double getStandardDeviation(); /** * Returns the maximum of the available values * @return The max or Double.NaN if no values have been added. */ double getMax(); /** * Returns the minimum of the available values * @return The min or Double.NaN if no values have been added. */ double getMin(); /** * Returns the number of available values * @return The number of available values */ long getN(); /** * Returns the sum of the values that have been added to Univariate. * @return The sum or Double.NaN if no values have been added */ double getSum(); }