Starting tests on field ODE! At least we can now run some code ...
Project: http://git-wip-us.apache.org/repos/asf/commons-math/repo Commit: http://git-wip-us.apache.org/repos/asf/commons-math/commit/87664da9 Tree: http://git-wip-us.apache.org/repos/asf/commons-math/tree/87664da9 Diff: http://git-wip-us.apache.org/repos/asf/commons-math/diff/87664da9 Branch: refs/heads/MATH_3_X Commit: 87664da98fb8586058973f4f9a50a5d231944f14 Parents: 07e2b94 Author: Luc Maisonobe <l...@apache.org> Authored: Tue Dec 1 12:23:20 2015 +0100 Committer: Luc Maisonobe <l...@apache.org> Committed: Tue Dec 1 12:23:20 2015 +0100 ---------------------------------------------------------------------- .../ode/nonstiff/EulerFieldIntegratorTest.java | 247 +++++++++++++++++++ 1 file changed, 247 insertions(+) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/commons-math/blob/87664da9/src/test/java/org/apache/commons/math3/ode/nonstiff/EulerFieldIntegratorTest.java ---------------------------------------------------------------------- diff --git a/src/test/java/org/apache/commons/math3/ode/nonstiff/EulerFieldIntegratorTest.java b/src/test/java/org/apache/commons/math3/ode/nonstiff/EulerFieldIntegratorTest.java new file mode 100644 index 0000000..2e41788 --- /dev/null +++ b/src/test/java/org/apache/commons/math3/ode/nonstiff/EulerFieldIntegratorTest.java @@ -0,0 +1,247 @@ +/* + * 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.math3.ode.nonstiff; + + +import java.lang.reflect.Array; + +import org.apache.commons.math3.Field; +import org.apache.commons.math3.RealFieldElement; +import org.apache.commons.math3.exception.DimensionMismatchException; +import org.apache.commons.math3.exception.MaxCountExceededException; +import org.apache.commons.math3.exception.NoBracketingException; +import org.apache.commons.math3.exception.NumberIsTooSmallException; +import org.apache.commons.math3.ode.FieldExpandableODE; +import org.apache.commons.math3.ode.FieldFirstOrderDifferentialEquations; +import org.apache.commons.math3.ode.FieldFirstOrderIntegrator; +import org.apache.commons.math3.ode.FieldODEState; +import org.apache.commons.math3.ode.FieldODEStateAndDerivative; +import org.apache.commons.math3.ode.TestFieldProblem1; +import org.apache.commons.math3.ode.TestFieldProblem2; +import org.apache.commons.math3.ode.TestFieldProblem3; +import org.apache.commons.math3.ode.TestFieldProblem4; +import org.apache.commons.math3.ode.TestFieldProblem5; +import org.apache.commons.math3.ode.TestFieldProblem6; +import org.apache.commons.math3.ode.TestFieldProblemAbstract; +import org.apache.commons.math3.ode.TestFieldProblemHandler; +import org.apache.commons.math3.ode.events.FieldEventHandler; +import org.apache.commons.math3.ode.sampling.FieldStepHandler; +import org.apache.commons.math3.ode.sampling.FieldStepInterpolator; +import org.apache.commons.math3.util.Decimal64Field; +import org.apache.commons.math3.util.FastMath; +import org.apache.commons.math3.util.MathArrays; +import org.junit.Assert; +import org.junit.Test; + +public class EulerFieldIntegratorTest { + + @Test(expected=DimensionMismatchException.class) + public void testDimensionCheck() + throws DimensionMismatchException, NumberIsTooSmallException, + MaxCountExceededException, NoBracketingException { + doTestDimensionCheck(Decimal64Field.getInstance()); + } + + private <T extends RealFieldElement<T>> void doTestDimensionCheck(Field<T> field) + throws DimensionMismatchException, NumberIsTooSmallException, + MaxCountExceededException, NoBracketingException { + TestFieldProblemAbstract<T> pb = new TestFieldProblem1<T>(field); + FieldExpandableODE<T> ode = new FieldExpandableODE<T>(pb); + FieldFirstOrderIntegrator<T> integ = + new EulerFieldIntegrator<T>(field, field.getZero().add(0.01)); + FieldODEState<T> start = + new FieldODEState<T>(field.getZero().add(0.0), + MathArrays.buildArray(field, pb.getDimension() + 10)); + integ.integrate(ode, start, field.getZero().add(1.0)); + } + + @Test + public void testDecreasingSteps() + throws DimensionMismatchException, NumberIsTooSmallException, + MaxCountExceededException, NoBracketingException { + dotTestDecreasingSteps(Decimal64Field.getInstance()); + } + + private <T extends RealFieldElement<T>> void dotTestDecreasingSteps(Field<T> field) + throws DimensionMismatchException, NumberIsTooSmallException, + MaxCountExceededException, NoBracketingException { + + @SuppressWarnings("unchecked") + TestFieldProblemAbstract<T>[] allProblems = + (TestFieldProblemAbstract<T>[]) Array.newInstance(TestFieldProblemAbstract.class, 6); + allProblems[0] = new TestFieldProblem1<T>(field); + allProblems[1] = new TestFieldProblem2<T>(field); + allProblems[2] = new TestFieldProblem3<T>(field); + allProblems[3] = new TestFieldProblem4<T>(field); + allProblems[4] = new TestFieldProblem5<T>(field); + allProblems[5] = new TestFieldProblem6<T>(field); + for (TestFieldProblemAbstract<T> pb : allProblems) { + + T previousValueError = null; + T previousTimeError = null; + for (int i = 4; i < 8; ++i) { + + T step = pb.getFinalTime().subtract(pb.getInitialState().getTime()).multiply(FastMath.pow(2.0, -i)); + + FieldFirstOrderIntegrator<T> integ = new EulerFieldIntegrator<T>(field, step); + TestFieldProblemHandler<T> handler = new TestFieldProblemHandler<T>(pb, integ); + integ.addStepHandler(handler); + FieldEventHandler<T>[] functions = pb.getEventsHandlers(); + for (int l = 0; l < functions.length; ++l) { + integ.addEventHandler(functions[l], + Double.POSITIVE_INFINITY, 1.0e-6 * step.getReal(), 1000); + } + FieldODEStateAndDerivative<T> stop = integ.integrate(new FieldExpandableODE<T>(pb), + pb.getInitialState(), + pb.getFinalTime()); + if (functions.length == 0) { + Assert.assertEquals(pb.getFinalTime().getReal(), stop.getTime().getReal(), 1.0e-10); + } + + T valueError = handler.getMaximalValueError(); + if (i > 4) { + Assert.assertTrue(valueError.subtract(previousValueError.abs()).getReal() < 0); + } + previousValueError = valueError; + + T timeError = handler.getMaximalTimeError(); + if (i > 4) { + Assert.assertTrue(timeError.subtract(previousTimeError.abs()).getReal() <= 0); + } + previousTimeError = timeError; + + } + + } + + } + + @Test + public void testSmallStep() + throws DimensionMismatchException, NumberIsTooSmallException, + MaxCountExceededException, NoBracketingException { + doTestSmallStep(Decimal64Field.getInstance()); + } + + private <T extends RealFieldElement<T>> void doTestSmallStep(Field<T> field) + throws DimensionMismatchException, NumberIsTooSmallException, + MaxCountExceededException, NoBracketingException { + + TestFieldProblem1<T> pb = new TestFieldProblem1<T>(field); + T step = pb.getFinalTime().subtract(pb.getInitialState().getTime()).multiply(0.001); + + FieldFirstOrderIntegrator<T> integ = new EulerFieldIntegrator<T>(field, step); + TestFieldProblemHandler<T> handler = new TestFieldProblemHandler<T>(pb, integ); + integ.addStepHandler(handler); + integ.integrate(new FieldExpandableODE<T>(pb), pb.getInitialState(), pb.getFinalTime()); + + Assert.assertTrue(handler.getLastError().getReal() < 2.0e-4); + Assert.assertTrue(handler.getMaximalValueError().getReal() < 1.0e-3); + Assert.assertEquals(0, handler.getMaximalTimeError().getReal(), 1.0e-12); + Assert.assertEquals("Euler", integ.getName()); + + } + + @Test + public void testBigStep() + throws DimensionMismatchException, NumberIsTooSmallException, + MaxCountExceededException, NoBracketingException { + doTestBigStep(Decimal64Field.getInstance()); + } + + private <T extends RealFieldElement<T>> void doTestBigStep(Field<T> field) + throws DimensionMismatchException, NumberIsTooSmallException, + MaxCountExceededException, NoBracketingException { + + TestFieldProblem1<T> pb = new TestFieldProblem1<T>(field); + T step = pb.getFinalTime().subtract(pb.getInitialState().getTime()).multiply(0.2); + + FieldFirstOrderIntegrator<T> integ = new EulerFieldIntegrator<T>(field, step); + TestFieldProblemHandler<T> handler = new TestFieldProblemHandler<T>(pb, integ); + integ.addStepHandler(handler); + integ.integrate(new FieldExpandableODE<T>(pb), pb.getInitialState(), pb.getFinalTime()); + + Assert.assertTrue(handler.getLastError().getReal() > 0.01); + Assert.assertTrue(handler.getMaximalValueError().getReal() > 0.2); + Assert.assertEquals(0, handler.getMaximalTimeError().getReal(), 1.0e-12); + + } + + @Test + public void testBackward() + throws DimensionMismatchException, NumberIsTooSmallException, + MaxCountExceededException, NoBracketingException { + doTestBackward(Decimal64Field.getInstance()); + } + + private <T extends RealFieldElement<T>> void doTestBackward(Field<T> field) + throws DimensionMismatchException, NumberIsTooSmallException, + MaxCountExceededException, NoBracketingException { + + TestFieldProblem5<T> pb = new TestFieldProblem5<T>(field); + T step = pb.getFinalTime().subtract(pb.getInitialState().getTime()).multiply(0.001).abs(); + + FieldFirstOrderIntegrator<T> integ = new EulerFieldIntegrator<T>(field, step); + TestFieldProblemHandler<T> handler = new TestFieldProblemHandler<T>(pb, integ); + integ.addStepHandler(handler); + integ.integrate(new FieldExpandableODE<>(pb), pb.getInitialState(), pb.getFinalTime()); + + Assert.assertTrue(handler.getLastError().getReal() < 0.45); + Assert.assertTrue(handler.getMaximalValueError().getReal() < 0.45); + Assert.assertEquals(0, handler.getMaximalTimeError().getReal(), 1.0e-12); + Assert.assertEquals("Euler", integ.getName()); + } + + @Test + public void testStepSize() + throws DimensionMismatchException, NumberIsTooSmallException, + MaxCountExceededException, NoBracketingException { + doTestStepSize(Decimal64Field.getInstance()); + } + + private <T extends RealFieldElement<T>> void doTestStepSize(Field<T> field) + throws DimensionMismatchException, NumberIsTooSmallException, + MaxCountExceededException, NoBracketingException { + final T step = field.getZero().add(1.23456); + FieldFirstOrderIntegrator<T> integ = new EulerFieldIntegrator<T>(field, step); + integ.addStepHandler(new FieldStepHandler<T>() { + public void handleStep(FieldStepInterpolator<T> interpolator, boolean isLast) { + if (! isLast) { + Assert.assertEquals(step.getReal(), + interpolator.getCurrentState().getTime().subtract(interpolator.getPreviousState().getTime()).getReal(), + 1.0e-12); + } + } + public void init(FieldODEStateAndDerivative<T> s0, T t) { + } + }); + integ.integrate(new FieldExpandableODE<T>(new FieldFirstOrderDifferentialEquations<T>() { + public void init(T t0, T[] y0, T t) { + } + public T[] computeDerivatives(T t, T[] y) { + T[] dot = MathArrays.buildArray(t.getField(), 1); + dot[0] = t.getField().getOne(); + return dot; + } + public int getDimension() { + return 1; + } + }), new FieldODEState<T>(field.getZero(), MathArrays.buildArray(field, 1)), field.getZero().add(5.0)); + } + +}
