@Test
public void testVariableSteps()
throws DimensionMismatchException, NumberIsTooSmallException, MaxCountExceededException,
NoBracketingException {
final TestProblem3 pb = new TestProblem3(0.9);
double minStep = 0;
double maxStep = pb.getFinalTime() - pb.getInitialTime();
double scalAbsoluteTolerance = 1.0e-8;
double scalRelativeTolerance = scalAbsoluteTolerance;
FirstOrderIntegrator integ =
new DormandPrince853Integrator(
minStep, maxStep, scalAbsoluteTolerance, scalRelativeTolerance);
integ.addStepHandler(new VariableHandler());
double stopTime =
integ.integrate(
pb,
pb.getInitialTime(),
pb.getInitialState(),
pb.getFinalTime(),
new double[pb.getDimension()]);
Assert.assertEquals(pb.getFinalTime(), stopTime, 1.0e-10);
Assert.assertEquals("Dormand-Prince 8 (5, 3)", integ.getName());
}
@Test
public void testBackward()
throws DimensionMismatchException, NumberIsTooSmallException, MaxCountExceededException,
NoBracketingException {
TestProblem5 pb = new TestProblem5();
double minStep = 0;
double maxStep = pb.getFinalTime() - pb.getInitialTime();
double scalAbsoluteTolerance = 1.0e-8;
double scalRelativeTolerance = 0.01 * scalAbsoluteTolerance;
FirstOrderIntegrator integ =
new DormandPrince853Integrator(
minStep, maxStep, scalAbsoluteTolerance, scalRelativeTolerance);
TestProblemHandler handler = new TestProblemHandler(pb, integ);
integ.addStepHandler(handler);
integ.integrate(
pb,
pb.getInitialTime(),
pb.getInitialState(),
pb.getFinalTime(),
new double[pb.getDimension()]);
Assert.assertTrue(handler.getLastError() < 1.1e-7);
Assert.assertTrue(handler.getMaximalValueError() < 1.1e-7);
Assert.assertEquals(0, handler.getMaximalTimeError(), 1.0e-12);
Assert.assertEquals("Dormand-Prince 8 (5, 3)", integ.getName());
}