| /* |
| * 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.apache.commons.math4.legacy.ode.events; |
| |
| import org.junit.Assert; |
| |
| import java.util.Arrays; |
| |
| import org.apache.commons.math4.legacy.analysis.solvers.PegasusSolver; |
| import org.apache.commons.math4.legacy.exception.DimensionMismatchException; |
| import org.apache.commons.math4.legacy.exception.MaxCountExceededException; |
| import org.apache.commons.math4.legacy.exception.NoBracketingException; |
| import org.apache.commons.math4.legacy.exception.NumberIsTooSmallException; |
| import org.apache.commons.math4.legacy.ode.FirstOrderDifferentialEquations; |
| import org.apache.commons.math4.legacy.ode.FirstOrderIntegrator; |
| import org.apache.commons.math4.legacy.ode.nonstiff.DormandPrince853Integrator; |
| import org.apache.commons.math4.legacy.ode.nonstiff.GraggBulirschStoerIntegrator; |
| import org.junit.Test; |
| |
| public class ReappearingEventTest { |
| @Test |
| public void testDormandPrince() |
| throws DimensionMismatchException, NumberIsTooSmallException, |
| MaxCountExceededException, NoBracketingException { |
| double tEnd = test(1); |
| Assert.assertEquals(10.0, tEnd, 1e-7); |
| } |
| |
| @Test |
| public void testGragg() |
| throws DimensionMismatchException, NumberIsTooSmallException, |
| MaxCountExceededException, NoBracketingException { |
| double tEnd = test(2); |
| Assert.assertEquals(10.0, tEnd, 1e-7); |
| } |
| |
| public double test(int integratorType) |
| throws DimensionMismatchException, NumberIsTooSmallException, |
| MaxCountExceededException, NoBracketingException { |
| double e = 1e-15; |
| FirstOrderIntegrator integrator; |
| integrator = (integratorType == 1) |
| ? new DormandPrince853Integrator(e, 100.0, 1e-7, 1e-7) |
| : new GraggBulirschStoerIntegrator(e, 100.0, 1e-7, 1e-7); |
| PegasusSolver rootSolver = new PegasusSolver(e, e); |
| integrator.addEventHandler(new Event(), 0.1, e, 1000, rootSolver); |
| double t0 = 6.0; |
| double tEnd = 10.0; |
| double[] y = {2.0, 2.0, 2.0, 4.0, 2.0, 7.0, 15.0}; |
| return integrator.integrate(new Ode(), t0, y, tEnd, y); |
| } |
| |
| private static class Ode implements FirstOrderDifferentialEquations { |
| @Override |
| public int getDimension() { |
| return 7; |
| } |
| |
| @Override |
| public void computeDerivatives(double t, double[] y, double[] yDot) { |
| Arrays.fill(yDot, 1.0); |
| } |
| } |
| |
| /** State events for this unit test. */ |
| protected static class Event implements EventHandler { |
| |
| @Override |
| public void init(double t0, double[] y0, double t) { |
| } |
| |
| @Override |
| public double g(double t, double[] y) { |
| return y[6] - 15.0; |
| } |
| |
| @Override |
| public Action eventOccurred(double t, double[] y, boolean increasing) { |
| return Action.STOP; |
| } |
| |
| @Override |
| public void resetState(double t, double[] y) { |
| // Never called. |
| } |
| } |
| } |