Interface ODEIntegrator

 All Known Implementing Classes:
AbstractIntegrator
,AdamsBashforthIntegrator
,AdamsIntegrator
,AdamsMoultonIntegrator
,AdaptiveStepsizeIntegrator
,ClassicalRungeKuttaIntegrator
,DormandPrince54Integrator
,DormandPrince853Integrator
,EmbeddedRungeKuttaIntegrator
,EulerIntegrator
,GillIntegrator
,GraggBulirschStoerIntegrator
,HighamHall54Integrator
,LutherIntegrator
,MidpointIntegrator
,MultistepIntegrator
,RungeKuttaIntegrator
,ThreeEighthesIntegrator
public interface ODEIntegrator
This interface represents a first order integrator for differential equations.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.


Method Summary
All Methods Instance Methods Abstract Methods Default Methods Deprecated Methods Modifier and Type Method 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 withgetStepStart()
.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 withintegrate(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.



Method Detail

getName
String getName()
Get the name of the method. Returns:
 name of the method

addStepHandler
void addStepHandler(ODEStepHandler handler)
Add a step handler to this integrator.The handler will be called by the integrator for each accepted step.
 Parameters:
handler
 handler for the accepted steps See Also:
getStepHandlers()
,clearStepHandlers()

getStepHandlers
Collection<ODEStepHandler> getStepHandlers()
Get all the step handlers that have been added to the integrator. Returns:
 an unmodifiable collection of the added events handlers
 See Also:
addStepHandler(ODEStepHandler)
,clearStepHandlers()

clearStepHandlers
void clearStepHandlers()
Remove all the step handlers that have been added to the integrator. See Also:
addStepHandler(ODEStepHandler)
,getStepHandlers()

addEventHandler
void addEventHandler(ODEEventHandler handler, double maxCheckInterval, double convergence, int maxIterationCount)
Add an event handler to the integrator.Uses a default
UnivariateSolver
with an absolute accuracy equal to the given convergence threshold, as rootfinding algorithm to detect the state events. Parameters:
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 thanmaxCheckInterval
and should be small compared to time scale of the ODE dynamics.maxIterationCount
 upper limit of the iteration count in the event time search See Also:
getEventHandlers()
,clearEventHandlers()

addEventHandler
void addEventHandler(ODEEventHandler handler, double maxCheckInterval, double convergence, int maxIterationCount, BracketedUnivariateSolver<UnivariateFunction> solver)
Add an event handler to the integrator. Parameters:
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 thanmaxCheckInterval
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. See Also:
getEventHandlers()
,clearEventHandlers()

getEventHandlers
Collection<ODEEventHandler> getEventHandlers()
Get all the event handlers that have been added to the integrator. Returns:
 an unmodifiable collection of the added events handlers
 See Also:
addEventHandler(ODEEventHandler, double, double, int)
,clearEventHandlers()

clearEventHandlers
void clearEventHandlers()
Remove all the event handlers that have been added to the integrator.

getCurrentStepStart
@Deprecated double getCurrentStepStart()
Deprecated.as of 1.0, replaced withgetStepStart()
.getTime()
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
. Returns:
 current value of the step start time t_{i}

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

getCurrentSignedStepsize
double 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
. Returns:
 current signed value of the stepsize

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

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

getEvaluations
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. Returns:
 number of evaluations of the differential equations function

integrate
ODEStateAndDerivative integrate(ExpandableODE equations, ODEState initialState, double finalTime) throws MathIllegalArgumentException, MathIllegalStateException
Integrate the differential equations up to the given time.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. Parameters:
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 thant0
for backward integration) Returns:
 final state, its time will be the same as
finalTime
if integration reached its target, but may be different if someODEEventHandler
stops it at some point.  Throws:
MathIllegalArgumentException
 if integration step is too smallMathIllegalStateException
 if the number of functions evaluations is exceededMathIllegalArgumentException
 if the location of an event cannot be bracketed

integrate
default ODEStateAndDerivative integrate(OrdinaryDifferentialEquation equations, ODEState initialState, double finalTime) throws MathIllegalArgumentException, MathIllegalStateException
Integrate the differential equations up to the given time.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. Parameters:
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 thant0
for backward integration) Returns:
 final state, its time will be the same as
finalTime
if integration reached its target, but may be different if someODEEventHandler
stops it at some point.  Throws:
MathIllegalArgumentException
 if integration step is too smallMathIllegalStateException
 if the number of functions evaluations is exceededMathIllegalArgumentException
 if the location of an event cannot be bracketed

integrate
@Deprecated default double integrate(OrdinaryDifferentialEquation equations, double t0, double[] y0, double t, double[] y) throws MathIllegalArgumentException, MathIllegalStateException
Deprecated.as of 1.0, replaced withintegrate(ExpandableODE, ODEState, double)
Integrate the differential equations up to the given time.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. Parameters:
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 thant0
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 y0 Returns:
 stop time, will be the same as target time if integration reached its
target, but may be different if some
ODEEventHandler
stops it at some point.  Throws:
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 bracketed

