| // Licensed to the Apache Software Foundation (ASF) under one |
| // or more contributor license agreements. See the NOTICE file |
| // distributed with this work for additional information |
| // regarding copyright ownership. The ASF licenses this file |
| // to you under the Apache License, Version 2.0 (the |
| // "License"); you may not use this file except in compliance |
| // with the License. You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, |
| // software distributed under the License is distributed on an |
| // "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| // KIND, either express or implied. See the License for the |
| // specific language governing permissions and limitations |
| // under the License. |
| |
| package org.spaceroots.mantissa.roots; |
| |
| import org.spaceroots.mantissa.functions.FunctionException; |
| |
| import junit.framework.*; |
| |
| public class BrentSolverTest |
| extends TestCase { |
| |
| public BrentSolverTest(String name) { |
| super(name); |
| } |
| |
| public void testAlefeldPotraShi() |
| throws FunctionException { |
| |
| TestProblem[] problems = TestProblem.getAPSProblems(); |
| BrentSolver solver = new BrentSolver(); |
| |
| for (int i = 0; i < problems.length; ++i) { |
| TestProblem p = problems[i]; |
| double tol = 1.0e-10 * Math.abs(p.getExpectedRoot()); |
| assertTrue(solver.findRoot(p, new Checker(tol), 1000, |
| p.getA(), p.valueAt(p.getA()), |
| p.getB(), p.valueAt(p.getB()))); |
| assertTrue(p.checkResult(solver.getRoot(), tol)); |
| } |
| |
| } |
| |
| private static class Checker implements ConvergenceChecker { |
| |
| private double tolerance; |
| |
| public Checker (double tolerance) { |
| this.tolerance = tolerance; |
| } |
| |
| public int converged (double xLow, double fLow, |
| double xHigh, double fHigh) { |
| return (Math.abs(xHigh - xLow) <= tolerance) |
| ? ((Math.abs(fLow) <= Math.abs(fHigh)) |
| ? ConvergenceChecker.LOW |
| : ConvergenceChecker.HIGH) |
| : ConvergenceChecker.NONE; |
| } |
| |
| } |
| |
| public static Test suite() { |
| return new TestSuite(BrentSolverTest.class); |
| } |
| |
| } |