This is the second half of this pr. Commit of analysis solver tests.
PR: http://nagoya.apache.org/bugzilla/show_bug.cgi?id=20844 Submitted by: J. Pietschman git-svn-id: https://svn.apache.org/repos/asf/jakarta/commons/proper/math/trunk@140944 13f79535-47bb-0310-9956-ffa450edef68
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/* ====================================================================
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* The Apache Software License, Version 1.1
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*
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* Copyright (c) 2003 The Apache Software Foundation. All rights
|
||||
* reserved.
|
||||
*
|
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* Redistribution and use in source and binary forms, with or without
|
||||
* modification, are permitted provided that the following conditions
|
||||
* are met:
|
||||
*
|
||||
* 1. Redistributions of source code must retain the above copyright
|
||||
* notice, this list of conditions and the following disclaimer.
|
||||
*
|
||||
* 2. Redistributions in binary form must reproduce the above copyright
|
||||
* notice, this list of conditions and the following disclaimer in
|
||||
* the documentation and/or other materials provided with the
|
||||
* distribution.
|
||||
*
|
||||
* 3. The end-user documentation included with the redistribution, if
|
||||
* any, must include the following acknowlegement:
|
||||
* "This product includes software developed by the
|
||||
* Apache Software Foundation (http://www.apache.org/)."
|
||||
* Alternately, this acknowlegement may appear in the software itself,
|
||||
* if and wherever such third-party acknowlegements normally appear.
|
||||
*
|
||||
* 4. The names "The Jakarta Project", "Commons", and "Apache Software
|
||||
* Foundation" must not be used to endorse or promote products derived
|
||||
* from this software without prior written permission. For written
|
||||
* permission, please contact apache@apache.org.
|
||||
*
|
||||
* 5. Products derived from this software may not be called "Apache"
|
||||
* nor may "Apache" appear in their names without prior written
|
||||
* permission of the Apache Software Foundation.
|
||||
*
|
||||
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
|
||||
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
|
||||
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
|
||||
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
|
||||
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
||||
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
|
||||
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
|
||||
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
|
||||
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
|
||||
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
|
||||
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
||||
* SUCH DAMAGE.
|
||||
* ====================================================================
|
||||
*
|
||||
* This software consists of voluntary contributions made by many
|
||||
* individuals on behalf of the Apache Software Foundation. For more
|
||||
* information on the Apache Software Foundation, please see
|
||||
* <http://www.apache.org/>.
|
||||
*/
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package org.apache.commons.math.analysis;
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import org.apache.commons.math.MathException;
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/**
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* Auxillary class for testing solvers.
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*
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* @author pietsch at apache.org
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*
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*/
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public class QuinticFunction implements UnivariateRealFunction {
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/* Evaluate quintic.
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* @see org.apache.commons.math.UnivariateRealFunction#value(double)
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*/
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public double value(double x) throws MathException {
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return (x-1)*(x-0.5)*x*(x+0.5)*(x+1);
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}
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/* First derivative of quintic.
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* @see org.apache.commons.math.UnivariateRealFunction#firstDerivative(double)
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*/
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public double firstDerivative(double x) throws MathException {
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return (5*x*x-3.75)*x*x+0.25;
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}
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/* Second order derivative of quintic.
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* Unsupported.
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* @see org.apache.commons.math.UnivariateRealFunction#secondDerivative(double)
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*/
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public double secondDerivative(double x) throws MathException {
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throw new UnsupportedOperationException();
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}
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}
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@ -0,0 +1,308 @@
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/* ====================================================================
|
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* The Apache Software License, Version 1.1
|
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*
|
||||
* Copyright (c) 2003 The Apache Software Foundation. All rights
|
||||
* reserved.
|
||||
*
|
||||
* Redistribution and use in source and binary forms, with or without
|
||||
* modification, are permitted provided that the following conditions
|
||||
* are met:
|
||||
*
|
||||
* 1. Redistributions of source code must retain the above copyright
|
||||
* notice, this list of conditions and the following disclaimer.
|
||||
*
|
||||
* 2. Redistributions in binary form must reproduce the above copyright
|
||||
* notice, this list of conditions and the following disclaimer in
|
||||
* the documentation and/or other materials provided with the
|
||||
* distribution.
|
||||
*
|
||||
* 3. The end-user documentation included with the redistribution, if
|
||||
* any, must include the following acknowlegement:
|
||||
* "This product includes software developed by the
|
||||
* Apache Software Foundation (http://www.apache.org/)."
|
||||
* Alternately, this acknowlegement may appear in the software itself,
|
||||
* if and wherever such third-party acknowlegements normally appear.
|
||||
*
|
||||
* 4. The names "The Jakarta Project", "Commons", and "Apache Software
|
||||
* Foundation" must not be used to endorse or promote products derived
|
||||
* from this software without prior written permission. For written
|
||||
* permission, please contact apache@apache.org.
|
||||
*
|
||||
* 5. Products derived from this software may not be called "Apache"
|
||||
* nor may "Apache" appear in their names without prior written
|
||||
* permission of the Apache Software Foundation.
|
||||
*
|
||||
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
|
||||
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
|
||||
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
|
||||
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
|
||||
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
||||
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
|
||||
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
|
||||
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
|
||||
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
|
||||
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
|
||||
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
||||
* SUCH DAMAGE.
|
||||
* ====================================================================
|
||||
*
|
||||
* This software consists of voluntary contributions made by many
|
||||
* individuals on behalf of the Apache Software Foundation. For more
|
||||
* information on the Apache Software Foundation, please see
|
||||
* <http://www.apache.org/>.
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*/
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package org.apache.commons.math.analysis;
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import org.apache.commons.math.MathException;
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import junit.framework.Assert;
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import junit.framework.Test;
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import junit.framework.TestCase;
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import junit.framework.TestSuite;
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/**
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* Testcase for UnivariateRealSolver.
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* Because Brent-Dekker is guaranteed to converge in less than the default
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* maximum iteration count due to bisection fallback, it is quite hard to
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* debug. I include measured iteration counts plus one in order to detect
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* regressions. On average Brent-Dekker should use 4..5 iterations for the
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* default absolute accuracy of 10E-8 for sinus and the quintic function around
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* zero, and 5..10 iterations for the other zeros.
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*
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* @author pietsch at apache.org
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*
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*/
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public final class RealSolverTest extends TestCase {
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public RealSolverTest(String name) {
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super(name);
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}
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public static Test suite() {
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TestSuite suite = new TestSuite(RealSolverTest.class);
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suite.setName("UnivariateRealSolver Tests");
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return suite;
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}
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public void testSinZero() throws MathException {
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// The sinus function is behaved well around the root at #pi. The second
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// order derivative is zero, which means linar approximating methods will
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// still converge quadratically.
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UnivariateRealFunction f = new SinFunction();
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double result;
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UnivariateRealSolver solver = new BrentSolver(f);
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// Somewhat benign interval. The function is monotonous.
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result = solver.solve(3, 4);
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System.out.println(
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"Root: " + result + " Iterations: " + solver.getIterationCount());
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assertEquals(result, Math.PI, solver.getAbsoluteAccuracy());
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// 4 iterations on i586 JDK 1.4.1.
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assertTrue(solver.getIterationCount() <= 5);
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// Larger and somewhat less benign interval. The function is grows first.
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result = solver.solve(1, 4);
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System.out.println(
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"Root: " + result + " Iterations: " + solver.getIterationCount());
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assertEquals(result, Math.PI, solver.getAbsoluteAccuracy());
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// 5 iterations on i586 JDK 1.4.1.
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assertTrue(solver.getIterationCount() <= 6);
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solver = new SecantSolver(f);
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result = solver.solve(3, 4);
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System.out.println(
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"Root: " + result + " Iterations: " + solver.getIterationCount());
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assertEquals(result, Math.PI, solver.getAbsoluteAccuracy());
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// 4 iterations on i586 JDK 1.4.1.
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assertTrue(solver.getIterationCount() <= 5);
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result = solver.solve(1, 4);
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System.out.println(
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"Root: " + result + " Iterations: " + solver.getIterationCount());
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assertEquals(result, Math.PI, solver.getAbsoluteAccuracy());
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// 5 iterations on i586 JDK 1.4.1.
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assertTrue(solver.getIterationCount() <= 6);
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}
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public void testQuinticZero() throws MathException {
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// The quintic function has zeroes at 0, +-0.5 and +-1.
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// Around the root of 0 the function is well behaved, with a second derivative
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// of zero a 0.
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// The other roots are less well to find, in particular the root at 1, because
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// the function grows fast for x>1.
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// The function has extrema (first derivative is zero) at 0.27195613 and 0.82221643,
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// intervals containing these values are harder for the solvers.
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UnivariateRealFunction f = new QuinticFunction();
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double result;
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// Brent-Dekker solver.
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UnivariateRealSolver solver = new BrentSolver(f);
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// Symmetric bracket around 0. Test whether solvers can handle hitting
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// the root in the first iteration.
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result = solver.solve(-0.2, 0.2);
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System.out.println(
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"Root: " + result + " Iterations: " + solver.getIterationCount());
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assertEquals(result, 0, solver.getAbsoluteAccuracy());
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assertTrue(solver.getIterationCount() <= 2);
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// 1 iterations on i586 JDK 1.4.1.
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// Asymmetric bracket around 0, just for fun. Contains extremum.
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result = solver.solve(-0.1, 0.3);
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System.out.println(
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"Root: " + result + " Iterations: " + solver.getIterationCount());
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assertEquals(result, 0, solver.getAbsoluteAccuracy());
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// 5 iterations on i586 JDK 1.4.1.
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assertTrue(solver.getIterationCount() <= 6);
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// Large bracket around 0. Contains two extrema.
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result = solver.solve(-0.3, 0.45);
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System.out.println(
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"Root: " + result + " Iterations: " + solver.getIterationCount());
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assertEquals(result, 0, solver.getAbsoluteAccuracy());
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// 6 iterations on i586 JDK 1.4.1.
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assertTrue(solver.getIterationCount() <= 7);
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// Benign bracket around 0.5, function is monotonous.
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result = solver.solve(0.3, 0.7);
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System.out.println(
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"Root: " + result + " Iterations: " + solver.getIterationCount());
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assertEquals(result, 0.5, solver.getAbsoluteAccuracy());
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// 6 iterations on i586 JDK 1.4.1.
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assertTrue(solver.getIterationCount() <= 7);
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// Less benign bracket around 0.5, contains one extremum.
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result = solver.solve(0.2, 0.6);
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System.out.println(
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"Root: " + result + " Iterations: " + solver.getIterationCount());
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assertEquals(result, 0.5, solver.getAbsoluteAccuracy());
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// 6 iterations on i586 JDK 1.4.1.
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assertTrue(solver.getIterationCount() <= 7);
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// Large, less benign bracket around 0.5, contains both extrema.
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result = solver.solve(0.05, 0.95);
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System.out.println(
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"Root: " + result + " Iterations: " + solver.getIterationCount());
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assertEquals(result, 0.5, solver.getAbsoluteAccuracy());
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// 8 iterations on i586 JDK 1.4.1.
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assertTrue(solver.getIterationCount() <= 9);
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// Relatively benign bracket around 1, function is monotonous. Fast growth for x>1
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// is still a problem.
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result = solver.solve(0.85, 1.25);
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System.out.println(
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"Root: " + result + " Iterations: " + solver.getIterationCount());
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assertEquals(result, 1.0, solver.getAbsoluteAccuracy());
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// 8 iterations on i586 JDK 1.4.1.
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assertTrue(solver.getIterationCount() <= 9);
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// Less benign bracket around 1 with extremum.
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result = solver.solve(0.8, 1.2);
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System.out.println(
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"Root: " + result + " Iterations: " + solver.getIterationCount());
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assertEquals(result, 1.0, solver.getAbsoluteAccuracy());
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// 8 iterations on i586 JDK 1.4.1.
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assertTrue(solver.getIterationCount() <= 9);
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// Large bracket around 1. Monotonous.
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result = solver.solve(0.85, 1.75);
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System.out.println(
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"Root: " + result + " Iterations: " + solver.getIterationCount());
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assertEquals(result, 1.0, solver.getAbsoluteAccuracy());
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// 10 iterations on i586 JDK 1.4.1.
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assertTrue(solver.getIterationCount() <= 11);
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// Large bracket around 1. Interval contains extremum.
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result = solver.solve(0.55, 1.45);
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System.out.println(
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"Root: " + result + " Iterations: " + solver.getIterationCount());
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assertEquals(result, 1.0, solver.getAbsoluteAccuracy());
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// 7 iterations on i586 JDK 1.4.1.
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assertTrue(solver.getIterationCount() <= 8);
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// Very large bracket around 1 for testing fast growth behaviour.
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result = solver.solve(0.85, 5);
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System.out.println(
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"Root: " + result + " Iterations: " + solver.getIterationCount());
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assertEquals(result, 1.0, solver.getAbsoluteAccuracy());
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// 12 iterations on i586 JDK 1.4.1.
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assertTrue(solver.getIterationCount() <= 13);
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// Secant solver.
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solver = new SecantSolver(f);
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result = solver.solve(-0.2, 0.2);
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System.out.println(
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"Root: " + result + " Iterations: " + solver.getIterationCount());
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assertEquals(result, 0, solver.getAbsoluteAccuracy());
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// 1 iterations on i586 JDK 1.4.1.
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assertTrue(solver.getIterationCount() <= 2);
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result = solver.solve(-0.1, 0.3);
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System.out.println(
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"Root: " + result + " Iterations: " + solver.getIterationCount());
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assertEquals(result, 0, solver.getAbsoluteAccuracy());
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// 5 iterations on i586 JDK 1.4.1.
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assertTrue(solver.getIterationCount() <= 6);
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result = solver.solve(-0.3, 0.45);
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System.out.println(
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"Root: " + result + " Iterations: " + solver.getIterationCount());
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assertEquals(result, 0, solver.getAbsoluteAccuracy());
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// 6 iterations on i586 JDK 1.4.1.
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assertTrue(solver.getIterationCount() <= 7);
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result = solver.solve(0.3, 0.7);
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System.out.println(
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"Root: " + result + " Iterations: " + solver.getIterationCount());
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assertEquals(result, 0.5, solver.getAbsoluteAccuracy());
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// 7 iterations on i586 JDK 1.4.1.
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assertTrue(solver.getIterationCount() <= 8);
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result = solver.solve(0.2, 0.6);
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System.out.println(
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"Root: " + result + " Iterations: " + solver.getIterationCount());
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assertEquals(result, 0.5, solver.getAbsoluteAccuracy());
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// 6 iterations on i586 JDK 1.4.1.
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assertTrue(solver.getIterationCount() <= 7);
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result = solver.solve(0.05, 0.95);
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System.out.println(
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"Root: " + result + " Iterations: " + solver.getIterationCount());
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assertEquals(result, 0.5, solver.getAbsoluteAccuracy());
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// 8 iterations on i586 JDK 1.4.1.
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assertTrue(solver.getIterationCount() <= 9);
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result = solver.solve(0.85, 1.25);
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System.out.println(
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"Root: " + result + " Iterations: " + solver.getIterationCount());
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assertEquals(result, 1.0, solver.getAbsoluteAccuracy());
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// 10 iterations on i586 JDK 1.4.1.
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assertTrue(solver.getIterationCount() <= 11);
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result = solver.solve(0.8, 1.2);
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System.out.println(
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"Root: " + result + " Iterations: " + solver.getIterationCount());
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assertEquals(result, 1.0, solver.getAbsoluteAccuracy());
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// 8 iterations on i586 JDK 1.4.1.
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assertTrue(solver.getIterationCount() <= 9);
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result = solver.solve(0.85, 1.75);
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System.out.println(
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"Root: " + result + " Iterations: " + solver.getIterationCount());
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assertEquals(result, 1.0, solver.getAbsoluteAccuracy());
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// 14 iterations on i586 JDK 1.4.1.
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assertTrue(solver.getIterationCount() <= 15);
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// The followig is especially slow because the solver first has to reduce
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// the bracket to exclude the extremum. After that, convergence is rapide.
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result = solver.solve(0.55, 1.45);
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System.out.println(
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"Root: " + result + " Iterations: " + solver.getIterationCount());
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assertEquals(result, 1.0, solver.getAbsoluteAccuracy());
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// 7 iterations on i586 JDK 1.4.1.
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assertTrue(solver.getIterationCount() <= 8);
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result = solver.solve(0.85, 5);
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System.out.println(
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"Root: " + result + " Iterations: " + solver.getIterationCount());
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assertEquals(result, 1.0, solver.getAbsoluteAccuracy());
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// 14 iterations on i586 JDK 1.4.1.
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assertTrue(solver.getIterationCount() <= 15);
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// Static solve method
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result = UnivariateRealSolverFactory.solve(f, -0.2, 0.2);
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assertEquals(result, 0, solver.getAbsoluteAccuracy());
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result = UnivariateRealSolverFactory.solve(f, -0.1, 0.3);
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Assert.assertEquals(result, 0, 1E-8);
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result = UnivariateRealSolverFactory.solve(f, -0.3, 0.45);
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Assert.assertEquals(result, 0, 1E-6);
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result = UnivariateRealSolverFactory.solve(f, 0.3, 0.7);
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Assert.assertEquals(result, 0.5, 1E-6);
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result = UnivariateRealSolverFactory.solve(f, 0.2, 0.6);
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Assert.assertEquals(result, 0.5, 1E-6);
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result = UnivariateRealSolverFactory.solve(f, 0.05, 0.95);
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Assert.assertEquals(result, 0.5, 1E-6);
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result = UnivariateRealSolverFactory.solve(f, 0.85, 1.25);
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Assert.assertEquals(result, 1.0, 1E-6);
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result = UnivariateRealSolverFactory.solve(f, 0.8, 1.2);
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Assert.assertEquals(result, 1.0, 1E-6);
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result = UnivariateRealSolverFactory.solve(f, 0.85, 1.75);
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Assert.assertEquals(result, 1.0, 1E-6);
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result = UnivariateRealSolverFactory.solve(f, 0.55, 1.45);
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Assert.assertEquals(result, 1.0, 1E-6);
|
||||
result = UnivariateRealSolverFactory.solve(f, 0.85, 5);
|
||||
Assert.assertEquals(result, 1.0, 1E-6);
|
||||
}
|
||||
}
|
|
@ -0,0 +1,93 @@
|
|||
/* ====================================================================
|
||||
* The Apache Software License, Version 1.1
|
||||
*
|
||||
* Copyright (c) 2003 The Apache Software Foundation. All rights
|
||||
* reserved.
|
||||
*
|
||||
* Redistribution and use in source and binary forms, with or without
|
||||
* modification, are permitted provided that the following conditions
|
||||
* are met:
|
||||
*
|
||||
* 1. Redistributions of source code must retain the above copyright
|
||||
* notice, this list of conditions and the following disclaimer.
|
||||
*
|
||||
* 2. Redistributions in binary form must reproduce the above copyright
|
||||
* notice, this list of conditions and the following disclaimer in
|
||||
* the documentation and/or other materials provided with the
|
||||
* distribution.
|
||||
*
|
||||
* 3. The end-user documentation included with the redistribution, if
|
||||
* any, must include the following acknowlegement:
|
||||
* "This product includes software developed by the
|
||||
* Apache Software Foundation (http://www.apache.org/)."
|
||||
* Alternately, this acknowlegement may appear in the software itself,
|
||||
* if and wherever such third-party acknowlegements normally appear.
|
||||
*
|
||||
* 4. The names "The Jakarta Project", "Commons", and "Apache Software
|
||||
* Foundation" must not be used to endorse or promote products derived
|
||||
* from this software without prior written permission. For written
|
||||
* permission, please contact apache@apache.org.
|
||||
*
|
||||
* 5. Products derived from this software may not be called "Apache"
|
||||
* nor may "Apache" appear in their names without prior written
|
||||
* permission of the Apache Software Foundation.
|
||||
*
|
||||
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
|
||||
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
|
||||
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
|
||||
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
|
||||
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
||||
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
|
||||
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
|
||||
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
|
||||
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
|
||||
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
|
||||
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
||||
* SUCH DAMAGE.
|
||||
* ====================================================================
|
||||
*
|
||||
* This software consists of voluntary contributions made by many
|
||||
* individuals on behalf of the Apache Software Foundation. For more
|
||||
* information on the Apache Software Foundation, please see
|
||||
* <http://www.apache.org/>.
|
||||
*/
|
||||
package org.apache.commons.math.analysis;
|
||||
|
||||
import org.apache.commons.math.MathException;
|
||||
|
||||
/**
|
||||
* Auxillary class for testing solvers.
|
||||
*
|
||||
* The function is extraordinarily well behaved around zero roots: it
|
||||
* has an inflection point there (second order derivative is zero),
|
||||
* which means linear approximation (Regula Falsi) will converge
|
||||
* quadratically.
|
||||
*
|
||||
* @author pietsch at apache.org
|
||||
*
|
||||
*/
|
||||
public class SinFunction implements UnivariateRealFunction {
|
||||
|
||||
/* Evaluate sinus fuction.
|
||||
* @see org.apache.commons.math.UnivariateRealFunction#value(double)
|
||||
*/
|
||||
public double value(double x) throws MathException {
|
||||
return Math.sin(x);
|
||||
}
|
||||
|
||||
/* First derivative of sinus function
|
||||
* @see org.apache.commons.math.UnivariateRealFunction#firstDerivative(double)
|
||||
*/
|
||||
public double firstDerivative(double x) throws MathException {
|
||||
return Math.cos(x);
|
||||
}
|
||||
|
||||
/* Second derivative of sinus function.
|
||||
* Unsupported.
|
||||
* @see org.apache.commons.math.UnivariateRealFunction#secondDerivative(double)
|
||||
*/
|
||||
public double secondDerivative(double x) throws MathException {
|
||||
throw new UnsupportedOperationException();
|
||||
}
|
||||
|
||||
}
|
Loading…
Reference in New Issue