public interface ODEIntegrator
The classes which are devoted to solve first order differential
equations should implement this interface. The problems which can
be handled should implement the OrdinaryDifferentialEquation
interface.
Modifier and Type  Method and Description 

void 
addEventHandler(ODEEventHandler handler,
double maxCheckInterval,
double convergence,
int maxIterationCount)
Add an event handler to the integrator.

void 
addEventHandler(ODEEventHandler handler,
double maxCheckInterval,
double convergence,
int maxIterationCount,
BracketedUnivariateSolver<UnivariateFunction> solver)
Add an event handler to the integrator.

void 
addStepHandler(ODEStepHandler 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.

double 
getCurrentSignedStepsize()
Get the current signed value of the integration stepsize.

double 
getCurrentStepStart()
Deprecated.
as of 1.0, replaced with
getStepStart() .getTime() 
int 
getEvaluations()
Get the number of evaluations of the differential equations function.

Collection<ODEEventHandler> 
getEventHandlers()
Get all the event handlers that have been added to the integrator.

int 
getMaxEvaluations()
Get the maximal number of functions evaluations.

String 
getName()
Get the name of the method.

Collection<ODEStepHandler> 
getStepHandlers()
Get all the step handlers that have been added to the integrator.

ODEStateAndDerivative 
getStepStart()
Get the state at step start time t_{i}.

ODEStateAndDerivative 
integrate(ExpandableODE equations,
ODEState initialState,
double finalTime)
Integrate the differential equations up to the given time.

default double 
integrate(OrdinaryDifferentialEquation equations,
double t0,
double[] y0,
double t,
double[] y)
Deprecated.
as of 1.0, replaced with
integrate(ExpandableODE, ODEState, double) 
default ODEStateAndDerivative 
integrate(OrdinaryDifferentialEquation equations,
ODEState initialState,
double finalTime)
Integrate the differential equations up to the given time.

void 
setMaxEvaluations(int maxEvaluations)
Set the maximal number of differential equations function evaluations.

String getName()
void addStepHandler(ODEStepHandler handler)
The handler will be called by the integrator for each accepted step.
handler
 handler for the accepted stepsgetStepHandlers()
,
clearStepHandlers()
Collection<ODEStepHandler> getStepHandlers()
addStepHandler(ODEStepHandler)
,
clearStepHandlers()
void clearStepHandlers()
addStepHandler(ODEStepHandler)
,
getStepHandlers()
void addEventHandler(ODEEventHandler handler, double maxCheckInterval, double convergence, int maxIterationCount)
Uses a default UnivariateSolver
with an absolute accuracy equal to the
given convergence threshold, as rootfinding algorithm to detect the state events.
handler
 event handlermaxCheckInterval
 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. Must be
smaller than maxCheckInterval
and should be small
compared to time scale of the ODE dynamics.maxIterationCount
 upper limit of the iteration count in the event time
searchgetEventHandlers()
,
clearEventHandlers()
void addEventHandler(ODEEventHandler handler, double maxCheckInterval, double convergence, int maxIterationCount, BracketedUnivariateSolver<UnivariateFunction> solver)
handler
 event handlermaxCheckInterval
 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. Must be
smaller than maxCheckInterval
and should be small
compared to time scale of the ODE dynamics.maxIterationCount
 upper limit of the iteration count in the event time
searchsolver
 The rootfinding algorithm to use to detect the state
events.getEventHandlers()
,
clearEventHandlers()
Collection<ODEEventHandler> getEventHandlers()
addEventHandler(ODEEventHandler, double, double, int)
,
clearEventHandlers()
void clearEventHandlers()
@Deprecated double getCurrentStepStart()
getStepStart()
.getTime()
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
.
ODEStateAndDerivative getStepStart()
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
.
double getCurrentSignedStepsize()
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
.
void setMaxEvaluations(int maxEvaluations)
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.
maxEvaluations
 maximal number of function evaluations (negative
values are silently converted to maximal integer value, thus representing
almost unlimited evaluations)int getMaxEvaluations()
int getEvaluations()
The number of evaluations corresponds to the last call to the
integrate
method. It is 0 if the method has not been called yet.
ODEStateAndDerivative integrate(ExpandableODE equations, ODEState initialState, double finalTime) throws MathIllegalArgumentException, MathIllegalStateException
This method solves an Initial Value Problem (IVP).
Since this method stores some internal state variables made
available in its public interface during integration (getCurrentSignedStepsize()
), it is not threadsafe.
equations
 differential equations to integrateinitialState
 initial state (time, primary and secondary state vectors)finalTime
 target time for the integration
(can be set to a value smaller than t0
for backward integration)finalTime
if
integration reached its target, but may be different if some ODEEventHandler
stops it at some point.MathIllegalArgumentException
 if integration step is too smallMathIllegalStateException
 if the number of functions evaluations is exceededMathIllegalArgumentException
 if the location of an event cannot be bracketeddefault ODEStateAndDerivative integrate(OrdinaryDifferentialEquation equations, ODEState initialState, double finalTime) throws MathIllegalArgumentException, MathIllegalStateException
This method solves an Initial Value Problem (IVP).
Since this method stores some internal state variables made
available in its public interface during integration (getCurrentSignedStepsize()
), it is not threadsafe.
equations
 differential equations to integrateinitialState
 initial state (time, primary and secondary state vectors)finalTime
 target time for the integration
(can be set to a value smaller than t0
for backward integration)finalTime
if
integration reached its target, but may be different if some ODEEventHandler
stops it at some point.MathIllegalArgumentException
 if integration step is too smallMathIllegalStateException
 if the number of functions evaluations is exceededMathIllegalArgumentException
 if the location of an event cannot be bracketed@Deprecated default double integrate(OrdinaryDifferentialEquation equations, double t0, double[] y0, double t, double[] y) throws MathIllegalArgumentException, MathIllegalStateException
integrate(ExpandableODE, ODEState, double)
This method solves an Initial Value Problem (IVP).
Since this method stores some internal state variables made
available in its public interface during integration (getCurrentSignedStepsize()
), it is not threadsafe.
equations
 differential equations to integratet0
 initial timey0
 initial value of the state vector at t0t
 target time for the integration
(can be set to a value smaller than t0
for backward integration)y
 placeholder where to put the state vector at each successful
step (and hence at the end of integration), can be the same object as y0ODEEventHandler
stops it at some point.MathIllegalArgumentException
 if arrays dimension do not match equations settingsMathIllegalArgumentException
 if integration step is too smallMathIllegalStateException
 if the number of functions evaluations is exceededMathIllegalArgumentException
 if the location of an event cannot be bracketedCopyright © 2016–2020 Hipparchus.org. All rights reserved.