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.moment;
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 KurtosisTest extends StorelessUnivariateStatisticAbstractTest{
30
31 protected Kurtosis stat;
32
33 /**
34 * @param name
35 */
36 public KurtosisTest(String name) {
37 super(name);
38 }
39
40 public static Test suite() {
41 TestSuite suite = new TestSuite(KurtosisTest.class);
42 suite.setName("Kurtosis Tests");
43 return suite;
44 }
45
46 /**
47 * {@inheritDoc}
48 */
49 @Override
50 public UnivariateStatistic getUnivariateStatistic() {
51 return new Kurtosis();
52 }
53
54 /**
55 * {@inheritDoc}
56 */
57 @Override
58 public double expectedValue() {
59 return this.kurt;
60 }
61
62 /**
63 * Make sure Double.NaN is returned iff n < 4
64 *
65 */
66 public void testNaN() {
67 Kurtosis kurt = new Kurtosis();
68 assertTrue(Double.isNaN(kurt.getResult()));
69 kurt.increment(1d);
70 assertTrue(Double.isNaN(kurt.getResult()));
71 kurt.increment(1d);
72 assertTrue(Double.isNaN(kurt.getResult()));
73 kurt.increment(1d);
74 assertTrue(Double.isNaN(kurt.getResult()));
75 kurt.increment(1d);
76 assertFalse(Double.isNaN(kurt.getResult()));
77 }
78
79 }