1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17 package org.apache.commons.math4.legacy.stat.descriptive;
18
19 /**
20 * Reporting interface for basic univariate statistics.
21 *
22 */
23 public interface StatisticalSummary {
24
25 /**
26 * Returns the <a href="http://www.xycoon.com/arithmetic_mean.htm">
27 * arithmetic mean </a> of the available values.
28 * @return The mean or Double.NaN if no values have been added.
29 */
30 double getMean();
31 /**
32 * Returns the variance of the available values.
33 * @return The variance, Double.NaN if no values have been added
34 * or 0.0 for a single value set.
35 */
36 double getVariance();
37 /**
38 * Returns the standard deviation of the available values.
39 * @return The standard deviation, Double.NaN if no values have been added
40 * or 0.0 for a single value set.
41 */
42 double getStandardDeviation();
43 /**
44 * Returns the maximum of the available values.
45 * @return The max or Double.NaN if no values have been added.
46 */
47 double getMax();
48 /**
49 * Returns the minimum of the available values.
50 * @return The min or Double.NaN if no values have been added.
51 */
52 double getMin();
53 /**
54 * Returns the number of available values.
55 * @return The number of available values
56 */
57 long getN();
58 /**
59 * Returns the sum of the values that have been added to Univariate.
60 * @return The sum or Double.NaN if no values have been added
61 */
62 double getSum();
63 }