org.apache.commons.math3.ode

Class AbstractFieldIntegrator<T extends RealFieldElement<T>>

java.lang.Object

org.apache.commons.math3.ode.AbstractFieldIntegrator<T>

Type Parameters:

T - the type of the field elements

All Implemented Interfaces:

FirstOrderFieldIntegrator<T>

Direct Known Subclasses:

AdaptiveStepsizeFieldIntegrator, RungeKuttaFieldIntegrator

public abstract class AbstractFieldIntegrator<T extends RealFieldElement<T>>
extends Object
implements FirstOrderFieldIntegrator<T>

Base class managing common boilerplate for all integrators.

Since:

3.6

Method Summary

Modifier and Type	Method and Description
void	addEventHandler(FieldEventHandler<T> handler, double maxCheckInterval, double convergence, int maxIterationCount) Add an event handler to the integrator.
void	addEventHandler(FieldEventHandler<T> handler, double maxCheckInterval, double convergence, int maxIterationCount, BracketedRealFieldUnivariateSolver<T> solver) Add an event handler to the integrator.
void	addStepHandler(FieldStepHandler<T> handler) Add a step handler to this integrator.
void	clearEventHandlers() Remove all the event handlers that have been added to the integrator.
void	clearStepHandlers() Remove all the step handlers that have been added to the integrator.
T[]	computeDerivatives(T t, T[] y) Compute the derivatives and check the number of evaluations.
T	getCurrentSignedStepsize() Get the current signed value of the integration stepsize.
FieldODEStateAndDerivative<T>	getCurrentStepStart() Get the current value of the step start time ti.
int	getEvaluations() Get the number of evaluations of the differential equations function.
Collection<FieldEventHandler<T>>	getEventHandlers() Get all the event handlers that have been added to the integrator.
Field<T>	getField() Get the field to which state vector elements belong.
int	getMaxEvaluations() Get the maximal number of functions evaluations.
String	getName() Get the name of the method.
Collection<FieldStepHandler<T>>	getStepHandlers() Get all the step handlers that have been added to the integrator.
void	setMaxEvaluations(int maxEvaluations) Set the maximal number of differential equations function evaluations.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.apache.commons.math3.ode.FirstOrderFieldIntegrator

integrate

Method Detail

getField

public Field<T> getField()

Get the field to which state vector elements belong.

Returns:

field to which state vector elements belong

getName

public String getName()

Get the name of the method.

Specified by:

getName in interface FirstOrderFieldIntegrator<T extends RealFieldElement<T>>

Returns:

name of the method

addStepHandler

public void addStepHandler(FieldStepHandler<T> handler)

Add a step handler to this integrator.

The handler will be called by the integrator for each accepted step.

Specified by:

addStepHandler in interface FirstOrderFieldIntegrator<T extends RealFieldElement<T>>

Parameters:

handler - handler for the accepted steps

See Also:

FirstOrderFieldIntegrator.getStepHandlers(), FirstOrderFieldIntegrator.clearStepHandlers()

getStepHandlers

public Collection<FieldStepHandler<T>> getStepHandlers()

Get all the step handlers that have been added to the integrator.

Specified by:

getStepHandlers in interface FirstOrderFieldIntegrator<T extends RealFieldElement<T>>

Returns:

an unmodifiable collection of the added events handlers

See Also:

FirstOrderFieldIntegrator.addStepHandler(FieldStepHandler), FirstOrderFieldIntegrator.clearStepHandlers()

clearStepHandlers

public void clearStepHandlers()

Remove all the step handlers that have been added to the integrator.

Specified by:

clearStepHandlers in interface FirstOrderFieldIntegrator<T extends RealFieldElement<T>>

See Also:

FirstOrderFieldIntegrator.addStepHandler(FieldStepHandler), FirstOrderFieldIntegrator.getStepHandlers()

addEventHandler

public void addEventHandler(FieldEventHandler<T> handler,
                            double maxCheckInterval,
                            double convergence,
                            int maxIterationCount)

Add an event handler to the integrator.

The default solver is a 5^th order FieldBracketingNthOrderBrentSolver.

Specified by:

addEventHandler in interface FirstOrderFieldIntegrator<T extends RealFieldElement<T>>

Parameters:

handler - event handler

maxCheckInterval - maximal time interval between switching function checks (this interval prevents missing sign changes in case the integration steps becomes very large)

convergence - convergence threshold in the event time search

maxIterationCount - upper limit of the iteration count in the event time search events.

See Also:

FirstOrderFieldIntegrator.addEventHandler(FieldEventHandler, double, double, int, org.apache.commons.math3.analysis.solvers.BracketedRealFieldUnivariateSolver), FirstOrderFieldIntegrator.getEventHandlers(), FirstOrderFieldIntegrator.clearEventHandlers()

addEventHandler

public void addEventHandler(FieldEventHandler<T> handler,
                            double maxCheckInterval,
                            double convergence,
                            int maxIterationCount,
                            BracketedRealFieldUnivariateSolver<T> solver)

Add an event handler to the integrator.

Specified by:

addEventHandler in interface FirstOrderFieldIntegrator<T extends RealFieldElement<T>>

Parameters:

handler - event handler

maxCheckInterval - maximal time interval between switching function checks (this interval prevents missing sign changes in case the integration steps becomes very large)

convergence - convergence threshold in the event time search

maxIterationCount - upper limit of the iteration count in the event time search events.

solver - solver to use to locate the event

See Also:

FirstOrderFieldIntegrator.addEventHandler(FieldEventHandler, double, double, int), FirstOrderFieldIntegrator.getEventHandlers(), FirstOrderFieldIntegrator.clearEventHandlers()

getEventHandlers

public Collection<FieldEventHandler<T>> getEventHandlers()

Get all the event handlers that have been added to the integrator.

Specified by:

getEventHandlers in interface FirstOrderFieldIntegrator<T extends RealFieldElement<T>>

Returns:

an unmodifiable collection of the added events handlers

See Also:

FirstOrderFieldIntegrator.addEventHandler(FieldEventHandler, double, double, int), FirstOrderFieldIntegrator.clearEventHandlers()

clearEventHandlers

public void clearEventHandlers()

Remove all the event handlers that have been added to the integrator.

Specified by:

clearEventHandlers in interface FirstOrderFieldIntegrator<T extends RealFieldElement<T>>

See Also:

FirstOrderFieldIntegrator.addEventHandler(FieldEventHandler, double, double, int), FirstOrderFieldIntegrator.getEventHandlers()

getCurrentStepStart

public FieldODEStateAndDerivative<T> getCurrentStepStart()

Get the current value of the step start time t_i.

This method can be called during integration (typically by the object implementing the differential equations problem) if the value of the current step that is attempted is needed.

The result is undefined if the method is called outside of calls to integrate.

Specified by:

getCurrentStepStart in interface FirstOrderFieldIntegrator<T extends RealFieldElement<T>>

Returns:

current value of the state at step start time t_i

getCurrentSignedStepsize

public T getCurrentSignedStepsize()

Get the current signed value of the integration stepsize.

This method can be called during integration (typically by the object implementing the differential equations problem) if the signed value of the current stepsize that is tried is needed.

The result is undefined if the method is called outside of calls to integrate.

Specified by:

getCurrentSignedStepsize in interface FirstOrderFieldIntegrator<T extends RealFieldElement<T>>

Returns:

current signed value of the stepsize

setMaxEvaluations

public void setMaxEvaluations(int maxEvaluations)

Set the maximal number of differential equations function evaluations.

The purpose of this method is to avoid infinite loops which can occur for example when stringent error constraints are set or when lots of discrete events are triggered, thus leading to many rejected steps.

Specified by:

setMaxEvaluations in interface FirstOrderFieldIntegrator<T extends RealFieldElement<T>>

Parameters:

maxEvaluations - maximal number of function evaluations (negative values are silently converted to maximal integer value, thus representing almost unlimited evaluations)

getMaxEvaluations

public int getMaxEvaluations()

Get the maximal number of functions evaluations.

Specified by:

getMaxEvaluations in interface FirstOrderFieldIntegrator<T extends RealFieldElement<T>>

Returns:

maximal number of functions evaluations

getEvaluations

public int getEvaluations()

Get the number of evaluations of the differential equations function.

The number of evaluations corresponds to the last call to the integrate method. It is 0 if the method has not been called yet.

Specified by:

getEvaluations in interface FirstOrderFieldIntegrator<T extends RealFieldElement<T>>

Returns:

number of evaluations of the differential equations function

computeDerivatives

public T[] computeDerivatives(T t,
                              T[] y)
                       throws DimensionMismatchException,
                              MaxCountExceededException,
                              NullPointerException

Compute the derivatives and check the number of evaluations.

Parameters:

t - current value of the independent time variable

y - array containing the current value of the state vector

Returns:

state completed with derivatives

Throws:

DimensionMismatchException - if arrays dimensions do not match equations settings

MaxCountExceededException - if the number of functions evaluations is exceeded

NullPointerException - if the ODE equations have not been set (i.e. if this method is called outside of a call to integrate