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.distribution;
18  
19  /**
20   * Test cases for PascalDistribution.
21   * Extends IntegerDistributionAbstractTest.  See class javadoc for
22   * IntegerDistributionAbstractTest for details.
23   * 
24   * @version $Revision:$ $Date:$
25   */
26  public class PascalDistributionTest extends IntegerDistributionAbstractTest {
27      
28      /**
29       * Constructor for PascalDistributionTest.
30       * @param name
31       */
32      public PascalDistributionTest(String name) {
33          super(name);
34      }
35      
36      //-------------- Implementations for abstract methods -----------------------
37      
38      /** Creates the default discrete distribution instance to use in tests. */
39      public IntegerDistribution makeDistribution() {
40          return new PascalDistributionImpl(10,0.70);
41      }
42      
43      /** Creates the default probability density test input values */
44      public int[] makeDensityTestPoints() {
45        return new int[] {-1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11};
46      }
47      
48      /** Creates the default probability density test expected values */
49      public double[] makeDensityTestValues() {
50        return new double[] {0d, 0.02824d, 0.08474d, 0.13982d, 
51            0.16779d, 0.16359d, 0.1374d, 0.10306d, 0.070673d, 0.04505d, 0.02703d, 0.01540d, 0.0084};
52      }
53      
54      /** Creates the default cumulative probability density test input values */
55      public int[] makeCumulativeTestPoints() {
56        return makeDensityTestPoints();
57      }
58      
59      /** Creates the default cumulative probability density test expected values */
60      public double[] makeCumulativeTestValues() {
61        return new double[] {0d, 0.02824d, 0.11299d, 0.25281d, 0.42060d, 0.58420d,
62            0.72162d, 0.82468d, 0.89535d, 0.94041d, 0.967446d, 0.98285, 0.99125d};
63          }
64      
65      /** Creates the default inverse cumulative probability test input values */
66      public double[] makeInverseCumulativeTestPoints() {
67        return new double[] {0, 0.001d, 0.010d, 0.025d, 0.050d, 0.100d, 0.999d,
68            0.990d, 0.975d, 0.950d, 0.900d, 1}; 
69          }
70      
71      /** Creates the default inverse cumulative probability density test expected values */
72      public int[] makeInverseCumulativeTestValues() {
73        return new int[] {-1, -1, -1, -1, 0, 0, 13, 10, 9, 8, 7, Integer.MAX_VALUE};
74      }
75  
76      //----------------- Additional test cases ---------------------------------
77     
78      /** Test degenerate case p = 0   */
79      public void testDegenerate0() throws Exception {
80          setDistribution(new PascalDistributionImpl(5,0.0d));
81          setCumulativeTestPoints(new int[] {-1, 0, 1, 5, 10 });
82          setCumulativeTestValues(new double[] {0d, 0d, 0d, 0d, 0d});
83          setDensityTestPoints(new int[] {-1, 0, 1, 10, 11});
84          setDensityTestValues(new double[] {0d, 0d, 0d, 0d, 0d});
85          setInverseCumulativeTestPoints(new double[] {0.1d, 0.5d});
86          setInverseCumulativeTestValues(new int[] {Integer.MAX_VALUE - 1, Integer.MAX_VALUE - 1});
87          verifyDensities();
88          verifyCumulativeProbabilities();
89          verifyInverseCumulativeProbabilities();     
90      }
91      
92      /** Test degenerate case p = 1   */
93      public void testDegenerate1() throws Exception {
94          setDistribution(new PascalDistributionImpl(5,1.0d));
95          setCumulativeTestPoints(new int[] {-1, 0, 1, 2, 5, 10 });
96          setCumulativeTestValues(new double[] {0d, 1d, 1d, 1d, 1d, 1d});
97          setDensityTestPoints(new int[] {-1, 0, 1, 2, 5, 10});
98          setDensityTestValues(new double[] {0d, 1d, 0d, 0d, 0d, 0d});
99          setInverseCumulativeTestPoints(new double[] {0.1d, 0.5d});
100         setInverseCumulativeTestValues(new int[] {-1, -1});
101         verifyDensities();
102         verifyCumulativeProbabilities();
103         verifyInverseCumulativeProbabilities();     
104     }
105 }