Apache
/
commons-math
mirror of https://github.com/apache/commons-math.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Fixed single integration step in step.

This commit is contained in:
Luc Maisonobe 2016-01-06 12:41:11 +01:00
parent 548dfd8bea
commit 5246aa0529
1 changed files with 41 additions and 33 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

74
src/test/java/org/apache/commons/math4/ode/nonstiff/AbstractRungeKuttaFieldStepInterpolatorTest.java
View File

@ -95,37 +95,7 @@ public abstract class AbstractRungeKuttaFieldStepInterpolatorTest {
RungeKuttaFieldStepInterpolator<T> interpolator = createInterpolator(field, t1 > t0, RungeKuttaFieldStepInterpolator<T> interpolator = createInterpolator(field, t1 > t0,
new FieldExpandableODE<T>(eqn).getMapper()); new FieldExpandableODE<T>(eqn).getMapper());
// get the Butcher arrays from the field integrator // get the Butcher arrays from the field integrator
String interpolatorName = interpolator.getClass().getName(); RungeKuttaFieldIntegrator<T> fieldIntegrator = createFieldIntegrator(field, interpolator);
String integratorName = interpolatorName.replaceAll("StepInterpolator", "Integrator");
RungeKuttaFieldIntegrator<T> fieldIntegrator = null;
try {
@SuppressWarnings("unchecked")
Class<RungeKuttaFieldIntegrator<T>> clz = (Class<RungeKuttaFieldIntegrator<T>>) Class.forName(integratorName);
try {
fieldIntegrator = clz.getConstructor(Field.class, RealFieldElement.class).newInstance(field,
field.getOne());
} catch (NoSuchMethodException nsme) {
try {
fieldIntegrator = clz.getConstructor(Field.class, RealFieldElement.class,
RealFieldElement.class, RealFieldElement.class).newInstance(field,
field.getZero().add(0.001),
field.getOne(),
field.getOne(),
field.getOne());
} catch (NoSuchMethodException e) {
Assert.fail(e.getLocalizedMessage());
}
}
} catch (InvocationTargetException ite) {
Assert.fail(ite.getLocalizedMessage());
} catch (IllegalAccessException iae) {
Assert.fail(iae.getLocalizedMessage());
} catch (InstantiationException ie) {
Assert.fail(ie.getLocalizedMessage());
} catch (ClassNotFoundException cnfe) {
Assert.fail(cnfe.getLocalizedMessage());
}
T[][] a = fieldIntegrator.getA(); T[][] a = fieldIntegrator.getA();
T[] b = fieldIntegrator.getB(); T[] b = fieldIntegrator.getB();
T[] c = fieldIntegrator.getC(); T[] c = fieldIntegrator.getC();
@ -146,8 +116,8 @@ public abstract class AbstractRungeKuttaFieldStepInterpolatorTest {
for (int k = 0; k < a.length; ++k) { for (int k = 0; k < a.length; ++k) {
for (int i = 0; i < y0.length; ++i) { for (int i = 0; i < y0.length; ++i) {
fieldY[i] = field.getZero().add(y0[i]); fieldY[i] = field.getZero().add(y0[i]);
for (int s = 0; s < k; ++s) { for (int s = 0; s <= k; ++s) {
fieldY[i] = fieldY[i].add(h.multiply(a[s][i].multiply(fieldYDotK[s][i]))); fieldY[i] = fieldY[i].add(h.multiply(a[k][s].multiply(fieldYDotK[s][i])));
} }
} }
fieldYDotK[k + 1] = eqn.computeDerivatives(h.multiply(c[k]).add(t0), fieldY); fieldYDotK[k + 1] = eqn.computeDerivatives(h.multiply(c[k]).add(t0), fieldY);
@ -169,6 +139,44 @@ public abstract class AbstractRungeKuttaFieldStepInterpolatorTest {
} }
private <T extends RealFieldElement<T>> RungeKuttaFieldIntegrator<T>
createFieldIntegrator(final Field<T> field, final RungeKuttaFieldStepInterpolator<T> interpolator) {
RungeKuttaFieldIntegrator<T> integrator = null;
try {
String interpolatorName = interpolator.getClass().getName();
String integratorName = interpolatorName.replaceAll("StepInterpolator", "Integrator");
@SuppressWarnings("unchecked")
Class<RungeKuttaFieldIntegrator<T>> clz = (Class<RungeKuttaFieldIntegrator<T>>) Class.forName(integratorName);
try {
integrator = clz.getConstructor(Field.class, RealFieldElement.class).newInstance(field,
field.getOne());
} catch (NoSuchMethodException nsme) {
try {
integrator = clz.getConstructor(Field.class,
RealFieldElement.class,
RealFieldElement.class,
RealFieldElement.class).
newInstance(field, field.getZero().add(0.001),
field.getOne(), field.getOne(), field.getOne());
} catch (NoSuchMethodException e) {
Assert.fail(e.getLocalizedMessage());
}
}
} catch (InvocationTargetException ite) {
Assert.fail(ite.getLocalizedMessage());
} catch (IllegalAccessException iae) {
Assert.fail(iae.getLocalizedMessage());
} catch (InstantiationException ie) {
Assert.fail(ie.getLocalizedMessage());
} catch (ClassNotFoundException cnfe) {
Assert.fail(cnfe.getLocalizedMessage());
}
return integrator;
}
private static class SinCos<T extends RealFieldElement<T>> implements FieldFirstOrderDifferentialEquations<T> { private static class SinCos<T extends RealFieldElement<T>> implements FieldFirstOrderDifferentialEquations<T> {
private final Field<T> field; private final Field<T> field;
protected SinCos(final Field<T> field) { protected SinCos(final Field<T> field) {