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 * https://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 18 /* 19 * This is not the original file distributed by the Apache Software Foundation 20 * It has been modified by the Hipparchus project 21 */ 22 23 package org.hipparchus.distribution.continuous; 24 25 import org.hipparchus.distribution.RealDistribution; 26 import org.junit.jupiter.api.BeforeEach; 27 import org.junit.jupiter.api.Test; 28 29 import static org.junit.jupiter.api.Assertions.assertEquals; 30 31 /** 32 * Test cases for ConstantRealDistribution. 33 */ 34 public class ConstantRealDistributionTest extends RealDistributionAbstractTest { 35 36 // --- Override tolerance ------------------------------------------------- 37 38 @BeforeEach 39 @Override 40 public void setUp() { 41 super.setUp(); 42 setTolerance(0); 43 } 44 45 //--- Implementations for abstract methods -------------------------------- 46 47 /** Creates the default uniform real distribution instance to use in tests. */ 48 @Override 49 public ConstantRealDistribution makeDistribution() { 50 return new ConstantRealDistribution(1); 51 } 52 53 /** Creates the default cumulative probability distribution test input values */ 54 @Override 55 public double[] makeCumulativeTestPoints() { 56 return new double[] { 0, 0.5, 1 }; 57 } 58 59 /** Creates the default cumulative probability distribution test expected values */ 60 @Override 61 public double[] makeCumulativeTestValues() { 62 return new double[] { 0, 0, 1 }; 63 } 64 65 /** Creates the default probability density test expected values */ 66 @Override 67 public double[] makeDensityTestValues() { 68 return new double[] { 0, 0, 1 }; 69 } 70 71 /** Override default test, verifying that inverse cum is constant */ 72 @Override 73 @Test 74 public void testInverseCumulativeProbabilities() { 75 RealDistribution dist = getDistribution(); 76 for (double x : getCumulativeTestValues()) { 77 assertEquals(1,dist.inverseCumulativeProbability(x), 0); 78 } 79 } 80 81 //--- Additional test cases ----------------------------------------------- 82 83 @Test 84 void testMeanVariance() { 85 ConstantRealDistribution dist; 86 87 dist = new ConstantRealDistribution(-1); 88 assertEquals(-1, dist.getNumericalMean(), 0d); 89 assertEquals(0, dist.getNumericalVariance(), 0d); 90 } 91 92 }