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.special;
018
019 import org.apache.commons.math.MathException;
020 import org.apache.commons.math.TestUtils;
021
022 import junit.framework.TestCase;
023
024 /**
025 * @version $Revision: 670469 $ $Date: 2008-06-23 04:01:38 -0400 (Mon, 23 Jun 2008) $
026 */
027 public class BetaTest extends TestCase {
028 /**
029 * Constructor for BetaTest.
030 * @param name
031 */
032 public BetaTest(String name) {
033 super(name);
034 }
035
036 private void testRegularizedBeta(double expected, double x, double a,
037 double b)
038 {
039 try {
040 double actual = Beta.regularizedBeta(x, a, b);
041 TestUtils.assertEquals(expected, actual, 10e-15);
042 } catch(MathException ex){
043 fail(ex.getMessage());
044 }
045 }
046
047 private void testLogBeta(double expected, double a, double b) {
048 double actual = Beta.logBeta(a, b);
049 TestUtils.assertEquals(expected, actual, 10e-15);
050 }
051
052 public void testRegularizedBetaNanPositivePositive() {
053 testRegularizedBeta(Double.NaN, Double.NaN, 1.0, 1.0);
054 }
055
056 public void testRegularizedBetaPositiveNanPositive() {
057 testRegularizedBeta(Double.NaN, 0.5, Double.NaN, 1.0);
058 }
059
060 public void testRegularizedBetaPositivePositiveNan() {
061 testRegularizedBeta(Double.NaN, 0.5, 1.0, Double.NaN);
062 }
063
064 public void testRegularizedBetaNegativePositivePositive() {
065 testRegularizedBeta(Double.NaN, -0.5, 1.0, 2.0);
066 }
067
068 public void testRegularizedBetaPositiveNegativePositive() {
069 testRegularizedBeta(Double.NaN, 0.5, -1.0, 2.0);
070 }
071
072 public void testRegularizedBetaPositivePositiveNegative() {
073 testRegularizedBeta(Double.NaN, 0.5, 1.0, -2.0);
074 }
075
076 public void testRegularizedBetaZeroPositivePositive() {
077 testRegularizedBeta(0.0, 0.0, 1.0, 2.0);
078 }
079
080 public void testRegularizedBetaPositiveZeroPositive() {
081 testRegularizedBeta(Double.NaN, 0.5, 0.0, 2.0);
082 }
083
084 public void testRegularizedBetaPositivePositiveZero() {
085 testRegularizedBeta(Double.NaN, 0.5, 1.0, 0.0);
086 }
087
088 public void testRegularizedBetaPositivePositivePositive() {
089 testRegularizedBeta(0.75, 0.5, 1.0, 2.0);
090 }
091
092 public void testLogBetaNanPositive() {
093 testLogBeta(Double.NaN, Double.NaN, 2.0);
094 }
095
096 public void testLogBetaPositiveNan() {
097 testLogBeta(Double.NaN, 1.0, Double.NaN);
098 }
099
100 public void testLogBetaNegativePositive() {
101 testLogBeta(Double.NaN, -1.0, 2.0);
102 }
103
104 public void testLogBetaPositiveNegative() {
105 testLogBeta(Double.NaN, 1.0, -2.0);
106 }
107
108 public void testLogBetaZeroPositive() {
109 testLogBeta(Double.NaN, 0.0, 2.0);
110 }
111
112 public void testLogBetaPositiveZero() {
113 testLogBeta(Double.NaN, 1.0, 0.0);
114 }
115
116 public void testLogBetaPositivePositive() {
117 testLogBeta(-0.693147180559945, 1.0, 2.0);
118 }
119 }