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.math.stat.descriptive.rank;
18  
19  import junit.framework.Test;
20  import junit.framework.TestSuite;
21  
22  import org.apache.commons.math.stat.descriptive.StorelessUnivariateStatisticAbstractTest;
23  import org.apache.commons.math.stat.descriptive.UnivariateStatistic;
24  
25  /**
26   * Test cases for the {@link UnivariateStatistic} class.
27   * @version $Revision: 762087 $ $Date: 2009-04-05 10:20:18 -0400 (Sun, 05 Apr 2009) $
28   */
29  public class MaxTest extends StorelessUnivariateStatisticAbstractTest{
30  
31      protected Max stat;
32      
33      /**
34       * @param name
35       */
36      public MaxTest(String name) {
37          super(name);
38      }
39  
40      public static Test suite() {
41          TestSuite suite = new TestSuite(MaxTest.class);
42          suite.setName("Max  Tests");
43          return suite;
44      }
45      
46      /**
47       * {@inheritDoc}
48       */
49      @Override
50      public UnivariateStatistic getUnivariateStatistic() {
51          return new Max();
52      }
53  
54      /**
55       * {@inheritDoc}
56       */
57      @Override
58      public double expectedValue() {
59          return this.max;
60      }
61      
62      public void testSpecialValues() {
63          double[] testArray = {0d, Double.NaN, Double.NEGATIVE_INFINITY, 
64                  Double.POSITIVE_INFINITY};
65          Max max = new Max();
66          assertTrue(Double.isNaN(max.getResult()));
67          max.increment(testArray[0]);
68          assertEquals(0d, max.getResult(), 0);
69          max.increment(testArray[1]);
70          assertEquals(0d, max.getResult(), 0);
71          max.increment(testArray[2]);
72          assertEquals(0d, max.getResult(), 0);
73          max.increment(testArray[3]);
74          assertEquals(Double.POSITIVE_INFINITY, max.getResult(), 0);
75          assertEquals(Double.POSITIVE_INFINITY, max.evaluate(testArray), 0);     
76      }
77  
78      public void testNaNs() {
79          Max max = new Max();
80          double nan = Double.NaN;
81          assertEquals(3d, max.evaluate(new double[]{nan, 2d, 3d}), 0);     
82          assertEquals(3d, max.evaluate(new double[]{1d, nan, 3d}), 0);     
83          assertEquals(2d, max.evaluate(new double[]{1d, 2d, nan}), 0);     
84          assertTrue(Double.isNaN(max.evaluate(new double[]{nan, nan, nan})));     
85      }
86  
87  }