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.stat.descriptive;
018
019
020 /**
021 * Base interface implemented by all statistics.
022 *
023 * @version $Revision: 811685 $ $Date: 2009-09-05 13:36:48 -0400 (Sat, 05 Sep 2009) $
024 */
025 public interface UnivariateStatistic {
026
027 /**
028 * Returns the result of evaluating the statistic over the input array.
029 *
030 * @param values input array
031 * @return the value of the statistic applied to the input array
032 */
033 double evaluate(double[] values);
034
035 /**
036 * Returns the result of evaluating the statistic over the specified entries
037 * in the input array.
038 *
039 * @param values the input array
040 * @param begin the index of the first element to include
041 * @param length the number of elements to include
042 * @return the value of the statistic applied to the included array entries
043 */
044 double evaluate(double[] values, int begin, int length);
045
046 /**
047 * Returns a copy of the statistic with the same internal state.
048 *
049 * @return a copy of the statistic
050 */
051 UnivariateStatistic copy();
052
053 }