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.analysis.solvers;
24
25 import org.hipparchus.analysis.UnivariateFunction;
26 import org.hipparchus.exception.MathIllegalStateException;
27 import org.hipparchus.util.FastMath;
28 import org.junit.Assert;
29 import org.junit.Test;
30
31 /**
32 * Test case for {@link RegulaFalsiSolver Regula Falsi} solver.
33 *
34 */
35 public final class RegulaFalsiSolverTest extends BaseSecantSolverAbstractTest {
36 /** {@inheritDoc} */
37 @Override
38 protected UnivariateSolver getSolver() {
39 UnivariateSolver solver = new RegulaFalsiSolver();
40 checktype(solver, BaseSecantSolver.Method.REGULA_FALSI);
41 return solver;
42 }
43
44 /** {@inheritDoc} */
45 @Override
46 protected int[] getQuinticEvalCounts() {
47 // While the Regula Falsi method guarantees convergence, convergence
48 // may be extremely slow. The last test case does not converge within
49 // even a million iterations. As such, it was disabled.
50 return new int[] {3, 7, 8, 19, 18, 11, 67, 55, 288, 151, -1};
51 }
52
53 @Test(expected=MathIllegalStateException.class)
54 public void testIssue631() {
55 final UnivariateFunction f = new UnivariateFunction() {
56 /** {@inheritDoc} */
57 public double value(double x) {
58 return FastMath.exp(x) - FastMath.pow(Math.PI, 3.0);
59 }
60 };
61
62 final UnivariateSolver solver = new RegulaFalsiSolver();
63 final double root = solver.solve(3624, f, 1, 10);
64 Assert.assertEquals(3.4341896575482003, root, 1e-15);
65 }
66 }