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.stat.ranking;
018    
019    import org.apache.commons.math.TestUtils;
020    import org.apache.commons.math.random.JDKRandomGenerator;
021    import org.apache.commons.math.random.RandomGenerator;
022    
023    import junit.framework.TestCase;
024    
025    /**
026     * Test cases for NaturalRanking class
027     * 
028     * @since 2.0
029     * @version $Revision: 799857 $ $Date: 2009-08-01 09:07:12 -0400 (Sat, 01 Aug 2009) $
030     */
031    public class NaturalRankingTest extends TestCase {
032    
033        private final double[] exampleData = { 20, 17, 30, 42.3, 17, 50,
034                Double.NaN, Double.NEGATIVE_INFINITY, 17 };
035        private final double[] tiesFirst = { 0, 0, 2, 1, 4 };
036        private final double[] tiesLast = { 4, 4, 1, 0 };
037        private final double[] multipleNaNs = { 0, 1, Double.NaN, Double.NaN };
038        private final double[] multipleTies = { 3, 2, 5, 5, 6, 6, 1 };
039        private final double[] allSame = { 0, 0, 0, 0 };
040    
041        public NaturalRankingTest(String arg0) {
042            super(arg0);
043        }
044    
045        @Override
046        protected void setUp() throws Exception {
047            super.setUp();
048        }
049    
050        @Override
051        protected void tearDown() throws Exception {
052            super.tearDown();
053        }
054    
055        public void testDefault() { // Ties averaged, NaNs maximal
056            NaturalRanking ranking = new NaturalRanking();
057            double[] ranks = ranking.rank(exampleData);
058            double[] correctRanks = { 5, 3, 6, 7, 3, 8, 9, 1, 3 };
059            TestUtils.assertEquals(correctRanks, ranks, 0d);
060            ranks = ranking.rank(tiesFirst);
061            correctRanks = new double[] { 1.5, 1.5, 4, 3, 5 };
062            TestUtils.assertEquals(correctRanks, ranks, 0d);
063            ranks = ranking.rank(tiesLast);
064            correctRanks = new double[] { 3.5, 3.5, 2, 1 };
065            TestUtils.assertEquals(correctRanks, ranks, 0d);
066            ranks = ranking.rank(multipleNaNs);
067            correctRanks = new double[] { 1, 2, 3.5, 3.5 };
068            TestUtils.assertEquals(correctRanks, ranks, 0d);
069            ranks = ranking.rank(multipleTies);
070            correctRanks = new double[] { 3, 2, 4.5, 4.5, 6.5, 6.5, 1 };
071            TestUtils.assertEquals(correctRanks, ranks, 0d);
072            ranks = ranking.rank(allSame);
073            correctRanks = new double[] { 2.5, 2.5, 2.5, 2.5 };
074            TestUtils.assertEquals(correctRanks, ranks, 0d);
075        }
076    
077        public void testNaNsMaximalTiesMinimum() {
078            NaturalRanking ranking = new NaturalRanking(TiesStrategy.MINIMUM);
079            double[] ranks = ranking.rank(exampleData);
080            double[] correctRanks = { 5, 2, 6, 7, 2, 8, 9, 1, 2 };
081            TestUtils.assertEquals(correctRanks, ranks, 0d);
082            ranks = ranking.rank(tiesFirst);
083            correctRanks = new double[] { 1, 1, 4, 3, 5 };
084            TestUtils.assertEquals(correctRanks, ranks, 0d);
085            ranks = ranking.rank(tiesLast);
086            correctRanks = new double[] { 3, 3, 2, 1 };
087            TestUtils.assertEquals(correctRanks, ranks, 0d);
088            ranks = ranking.rank(multipleNaNs);
089            correctRanks = new double[] { 1, 2, 3, 3 };
090            TestUtils.assertEquals(correctRanks, ranks, 0d);
091            ranks = ranking.rank(multipleTies);
092            correctRanks = new double[] { 3, 2, 4, 4, 6, 6, 1 };
093            TestUtils.assertEquals(correctRanks, ranks, 0d);
094            ranks = ranking.rank(allSame);
095            correctRanks = new double[] { 1, 1, 1, 1 };
096            TestUtils.assertEquals(correctRanks, ranks, 0d);
097        }
098    
099        public void testNaNsRemovedTiesSequential() {
100            NaturalRanking ranking = new NaturalRanking(NaNStrategy.REMOVED,
101                    TiesStrategy.SEQUENTIAL);
102            double[] ranks = ranking.rank(exampleData);
103            double[] correctRanks = { 5, 2, 6, 7, 3, 8, 1, 4 };
104            TestUtils.assertEquals(correctRanks, ranks, 0d);
105            ranks = ranking.rank(tiesFirst);
106            correctRanks = new double[] { 1, 2, 4, 3, 5 };
107            TestUtils.assertEquals(correctRanks, ranks, 0d);
108            ranks = ranking.rank(tiesLast);
109            correctRanks = new double[] { 3, 4, 2, 1 };
110            TestUtils.assertEquals(correctRanks, ranks, 0d);
111            ranks = ranking.rank(multipleNaNs);
112            correctRanks = new double[] { 1, 2 };
113            TestUtils.assertEquals(correctRanks, ranks, 0d);
114            ranks = ranking.rank(multipleTies);
115            correctRanks = new double[] { 3, 2, 4, 5, 6, 7, 1 };
116            TestUtils.assertEquals(correctRanks, ranks, 0d);
117            ranks = ranking.rank(allSame);
118            correctRanks = new double[] { 1, 2, 3, 4 };
119            TestUtils.assertEquals(correctRanks, ranks, 0d);
120        }
121    
122        public void testNaNsMinimalTiesMaximum() {
123            NaturalRanking ranking = new NaturalRanking(NaNStrategy.MINIMAL,
124                    TiesStrategy.MAXIMUM);
125            double[] ranks = ranking.rank(exampleData);
126            double[] correctRanks = { 6, 5, 7, 8, 5, 9, 2, 2, 5 };
127            TestUtils.assertEquals(correctRanks, ranks, 0d);
128            ranks = ranking.rank(tiesFirst);
129            correctRanks = new double[] { 2, 2, 4, 3, 5 };
130            TestUtils.assertEquals(correctRanks, ranks, 0d);
131            ranks = ranking.rank(tiesLast);
132            correctRanks = new double[] { 4, 4, 2, 1 };
133            TestUtils.assertEquals(correctRanks, ranks, 0d);
134            ranks = ranking.rank(multipleNaNs);
135            correctRanks = new double[] { 3, 4, 2, 2 };
136            TestUtils.assertEquals(correctRanks, ranks, 0d);
137            ranks = ranking.rank(multipleTies);
138            correctRanks = new double[] { 3, 2, 5, 5, 7, 7, 1 };
139            TestUtils.assertEquals(correctRanks, ranks, 0d);
140            ranks = ranking.rank(allSame);
141            correctRanks = new double[] { 4, 4, 4, 4 };
142            TestUtils.assertEquals(correctRanks, ranks, 0d);
143        }
144    
145        public void testNaNsMinimalTiesAverage() {
146            NaturalRanking ranking = new NaturalRanking(NaNStrategy.MINIMAL);
147            double[] ranks = ranking.rank(exampleData);
148            double[] correctRanks = { 6, 4, 7, 8, 4, 9, 1.5, 1.5, 4 };
149            TestUtils.assertEquals(correctRanks, ranks, 0d);
150            ranks = ranking.rank(tiesFirst);
151            correctRanks = new double[] { 1.5, 1.5, 4, 3, 5 };
152            TestUtils.assertEquals(correctRanks, ranks, 0d);
153            ranks = ranking.rank(tiesLast);
154            correctRanks = new double[] { 3.5, 3.5, 2, 1 };
155            TestUtils.assertEquals(correctRanks, ranks, 0d);
156            ranks = ranking.rank(multipleNaNs);
157            correctRanks = new double[] { 3, 4, 1.5, 1.5 };
158            TestUtils.assertEquals(correctRanks, ranks, 0d);
159            ranks = ranking.rank(multipleTies);
160            correctRanks = new double[] { 3, 2, 4.5, 4.5, 6.5, 6.5, 1 };
161            TestUtils.assertEquals(correctRanks, ranks, 0d);
162            ranks = ranking.rank(allSame);
163            correctRanks = new double[] { 2.5, 2.5, 2.5, 2.5 };
164            TestUtils.assertEquals(correctRanks, ranks, 0d);
165        }
166    
167        public void testNaNsFixedTiesRandom() {
168            RandomGenerator randomGenerator = new JDKRandomGenerator();
169            randomGenerator.setSeed(1000);
170            NaturalRanking ranking = new NaturalRanking(NaNStrategy.FIXED,
171                    randomGenerator);
172            double[] ranks = ranking.rank(exampleData);
173            double[] correctRanks = { 5, 4, 6, 7, 3, 8, Double.NaN, 1, 4 };
174            TestUtils.assertEquals(correctRanks, ranks, 0d);
175            ranks = ranking.rank(tiesFirst);
176            correctRanks = new double[] { 1, 1, 4, 3, 5 };
177            TestUtils.assertEquals(correctRanks, ranks, 0d);
178            ranks = ranking.rank(tiesLast);
179            correctRanks = new double[] { 3, 4, 2, 1 };
180            TestUtils.assertEquals(correctRanks, ranks, 0d);
181            ranks = ranking.rank(multipleNaNs);
182            correctRanks = new double[] { 1, 2, Double.NaN, Double.NaN };
183            TestUtils.assertEquals(correctRanks, ranks, 0d);
184            ranks = ranking.rank(multipleTies);
185            correctRanks = new double[] { 3, 2, 5, 5, 7, 6, 1 };
186            TestUtils.assertEquals(correctRanks, ranks, 0d);
187            ranks = ranking.rank(allSame);
188            correctRanks = new double[] { 1, 3, 4, 4 };
189            TestUtils.assertEquals(correctRanks, ranks, 0d);
190        }
191    
192        public void testNaNsAndInfs() {
193            double[] data = { 0, Double.POSITIVE_INFINITY, Double.NaN,
194                    Double.NEGATIVE_INFINITY };
195            NaturalRanking ranking = new NaturalRanking(NaNStrategy.MAXIMAL);
196            double[] ranks = ranking.rank(data);
197            double[] correctRanks = new double[] { 2, 3.5, 3.5, 1 };
198            TestUtils.assertEquals(correctRanks, ranks, 0d);
199            ranking = new NaturalRanking(NaNStrategy.MINIMAL);
200            ranks = ranking.rank(data);
201            correctRanks = new double[] { 3, 4, 1.5, 1.5 };
202            TestUtils.assertEquals(correctRanks, ranks, 0d);
203        }
204    }