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.distribution;
018    
019    /**
020     * Test cases for BinomialDistribution.
021     * Extends IntegerDistributionAbstractTest.  See class javadoc for
022     * IntegerDistributionAbstractTest for details.
023     * 
024     * @version $Revision: 762087 $ $Date: 2009-04-05 10:20:18 -0400 (Sun, 05 Apr 2009) $
025     */
026    public class BinomialDistributionTest extends IntegerDistributionAbstractTest {
027        
028        /**
029         * Constructor for BinomialDistributionTest.
030         * @param name
031         */
032        public BinomialDistributionTest(String name) {
033            super(name);
034        }
035        
036        //-------------- Implementations for abstract methods -----------------------
037        
038        /** Creates the default discrete distribution instance to use in tests. */
039        @Override
040        public IntegerDistribution makeDistribution() {
041            return new BinomialDistributionImpl(10,0.70);
042        }
043        
044        /** Creates the default probability density test input values */
045        @Override
046        public int[] makeDensityTestPoints() {
047            return new int[] {-1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11};
048        }
049        
050        /** Creates the default probability density test expected values */
051        @Override
052        public double[] makeDensityTestValues() {
053            return new double[] {0d, 0.0000d, 0.0001d, 0.0014d, 0.0090d, 0.0368d, 0.1029d, 
054                    0.2001d, 0.2668d, 0.2335d, 0.1211d, 0.0282d, 0d};
055        }
056        
057        /** Creates the default cumulative probability density test input values */
058        @Override
059        public int[] makeCumulativeTestPoints() {
060            return makeDensityTestPoints();
061        }
062        
063        /** Creates the default cumulative probability density test expected values */
064        @Override
065        public double[] makeCumulativeTestValues() {
066            return new double[] {0d, 0.0000d, 0.0001d, 0.0016d, 0.0106d, 0.0473d,
067                    0.1503d, 0.3504d, 0.6172d, 0.8507d, 0.9718d, 1d, 1d};
068            }
069        
070        /** Creates the default inverse cumulative probability test input values */
071        @Override
072        public double[] makeInverseCumulativeTestPoints() {
073            return new double[] {0, 0.001d, 0.010d, 0.025d, 0.050d, 0.100d, 0.999d,
074                    0.990d, 0.975d, 0.950d, 0.900d,1}; 
075            }
076        
077        /** Creates the default inverse cumulative probability density test expected values */
078        @Override
079        public int[] makeInverseCumulativeTestValues() {
080            return new int[] {-1, 1, 2, 3, 4, 4, 9, 9, 9, 8, 8, Integer.MAX_VALUE};
081        }
082    
083        //----------------- Additional test cases ---------------------------------
084       
085        /** Test degenerate case p = 0   */
086        public void testDegenerate0() throws Exception {
087            setDistribution(new BinomialDistributionImpl(5,0.0d));
088            setCumulativeTestPoints(new int[] {-1, 0, 1, 5, 10 });
089            setCumulativeTestValues(new double[] {0d, 1d, 1d, 1d, 1d});
090            setDensityTestPoints(new int[] {-1, 0, 1, 10, 11});
091            setDensityTestValues(new double[] {0d, 1d, 0d, 0d, 0d});
092            setInverseCumulativeTestPoints(new double[] {0.1d, 0.5d});
093            setInverseCumulativeTestValues(new int[] {-1, -1});
094            verifyDensities();
095            verifyCumulativeProbabilities();
096            verifyInverseCumulativeProbabilities();     
097        }
098        
099        /** Test degenerate case p = 1   */
100        public void testDegenerate1() throws Exception {
101            setDistribution(new BinomialDistributionImpl(5,1.0d));
102            setCumulativeTestPoints(new int[] {-1, 0, 1, 2, 5, 10 });
103            setCumulativeTestValues(new double[] {0d, 0d, 0d, 0d, 1d, 1d});
104            setDensityTestPoints(new int[] {-1, 0, 1, 2, 5, 10});
105            setDensityTestValues(new double[] {0d, 0d, 0d, 0d, 1d, 0d});
106            setInverseCumulativeTestPoints(new double[] {0.1d, 0.5d});
107            setInverseCumulativeTestValues(new int[] {4, 4});
108            verifyDensities();
109            verifyCumulativeProbabilities();
110            verifyInverseCumulativeProbabilities();     
111        }
112    
113    }