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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    *      https://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  
18  /*
19   * This is not the original file distributed by the Apache Software Foundation
20   * It has been modified by the Hipparchus project
21   */
22  package org.hipparchus.stat.descriptive.moment;
23  
24  import org.hipparchus.stat.descriptive.StorelessUnivariateStatisticAbstractTest;
25  import org.junit.jupiter.api.Test;
26  
27  import static org.junit.jupiter.api.Assertions.assertEquals;
28  import static org.junit.jupiter.api.Assertions.assertFalse;
29  import static org.junit.jupiter.api.Assertions.assertTrue;
30  
31  /**
32   * Test cases for the {@link GeometricMean} class.
33   */
34  public class GeometricMeanTest extends StorelessUnivariateStatisticAbstractTest{
35  
36      @Override
37      public GeometricMean getUnivariateStatistic() {
38          return new GeometricMean();
39      }
40  
41      @Override
42      public double expectedValue() {
43          return this.geoMean;
44      }
45  
46      @Test
47      void testSpecialValues() {
48          GeometricMean mean = getUnivariateStatistic();
49          // empty
50          assertTrue(Double.isNaN(mean.getResult()));
51  
52          // finite data
53          mean.increment(1d);
54          assertFalse(Double.isNaN(mean.getResult()));
55  
56          // add 0 -- makes log sum blow to minus infinity, should make 0
57          mean.increment(0d);
58          assertEquals(0d, mean.getResult(), 0);
59  
60          // add positive infinity - note the minus infinity above
61          mean.increment(Double.POSITIVE_INFINITY);
62          assertTrue(Double.isNaN(mean.getResult()));
63  
64          // clear
65          mean.clear();
66          assertTrue(Double.isNaN(mean.getResult()));
67  
68          // positive infinity by itself
69          mean.increment(Double.POSITIVE_INFINITY);
70          assertEquals(Double.POSITIVE_INFINITY, mean.getResult(), 0);
71  
72          // negative value -- should make NaN
73          mean.increment(-2d);
74          assertTrue(Double.isNaN(mean.getResult()));
75      }
76  
77  }