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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  package org.hipparchus.analysis.solvers;
23  
24  import org.hipparchus.analysis.QuinticFunction;
25  import org.hipparchus.analysis.UnivariateFunction;
26  import org.hipparchus.analysis.function.Sin;
27  import org.hipparchus.exception.MathIllegalArgumentException;
28  import org.hipparchus.util.FastMath;
29  import org.junit.Assert;
30  import org.junit.Test;
31  
32  /**
33   */
34  public final class BisectionSolverTest {
35      @Test
36      public void testSinZero() {
37          UnivariateFunction f = new Sin();
38          double result;
39  
40          BisectionSolver solver = new BisectionSolver();
41          result = solver.solve(100, f, 3, 4);
42          Assert.assertEquals(result, FastMath.PI, solver.getAbsoluteAccuracy());
43  
44          result = solver.solve(100, f, 1, 4);
45          Assert.assertEquals(result, FastMath.PI, solver.getAbsoluteAccuracy());
46      }
47  
48      @Test
49      public void testQuinticZero() {
50          UnivariateFunction f = new QuinticFunction();
51          double result;
52  
53          BisectionSolver solver = new BisectionSolver();
54          result = solver.solve(100, f, -0.2, 0.2);
55          Assert.assertEquals(result, 0, solver.getAbsoluteAccuracy());
56  
57          result = solver.solve(100, f, -0.1, 0.3);
58          Assert.assertEquals(result, 0, solver.getAbsoluteAccuracy());
59  
60          result = solver.solve(100, f, -0.3, 0.45);
61          Assert.assertEquals(result, 0, solver.getAbsoluteAccuracy());
62  
63          result = solver.solve(100, f, 0.3, 0.7);
64          Assert.assertEquals(result, 0.5, solver.getAbsoluteAccuracy());
65  
66          result = solver.solve(100, f, 0.2, 0.6);
67          Assert.assertEquals(result, 0.5, solver.getAbsoluteAccuracy());
68  
69          result = solver.solve(100, f, 0.05, 0.95);
70          Assert.assertEquals(result, 0.5, solver.getAbsoluteAccuracy());
71  
72          result = solver.solve(100, f, 0.85, 1.25);
73          Assert.assertEquals(result, 1.0, solver.getAbsoluteAccuracy());
74  
75          result = solver.solve(100, f, 0.8, 1.2);
76          Assert.assertEquals(result, 1.0, solver.getAbsoluteAccuracy());
77  
78          result = solver.solve(100, f, 0.85, 1.75);
79          Assert.assertEquals(result, 1.0, solver.getAbsoluteAccuracy());
80  
81          result = solver.solve(100, f, 0.55, 1.45);
82          Assert.assertEquals(result, 1.0, solver.getAbsoluteAccuracy());
83  
84          result = solver.solve(100, f, 0.85, 5);
85          Assert.assertEquals(result, 1.0, solver.getAbsoluteAccuracy());
86  
87          Assert.assertTrue(solver.getEvaluations() > 0);
88      }
89  
90      @Test
91      public void testMath369() {
92          UnivariateFunction f = new Sin();
93          BisectionSolver solver = new BisectionSolver();
94          Assert.assertEquals(FastMath.PI, solver.solve(100, f, 3.0, 3.2, 3.1), solver.getAbsoluteAccuracy());
95      }
96  
97      @Test(expected= MathIllegalArgumentException.class)
98      public void testHipparchusGithub40() {
99          new BisectionSolver().solve(100, x -> Math.cos(x) + 2, 0.0, 5.0);
100     }
101 
102 }
103