Package org.apache.commons.math3.ode

Interface FirstOrderFieldIntegrator<T extends RealFieldElement<T>>

Type Parameters:
T - the type of the field elements
All Known Implementing Classes:
AbstractFieldIntegrator, AdamsBashforthFieldIntegrator, AdamsFieldIntegrator, AdamsMoultonFieldIntegrator, AdaptiveStepsizeFieldIntegrator, ClassicalRungeKuttaFieldIntegrator, DormandPrince54FieldIntegrator, DormandPrince853FieldIntegrator, EmbeddedRungeKuttaFieldIntegrator, EulerFieldIntegrator, GillFieldIntegrator, HighamHall54FieldIntegrator, LutherFieldIntegrator, MidpointFieldIntegrator, MultistepFieldIntegrator, RungeKuttaFieldIntegrator, ThreeEighthesFieldIntegrator
public interface FirstOrderFieldIntegrator<T extends RealFieldElement<T>>
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 FirstOrderDifferentialEquations interface.

Since:
3.6
See Also:

  • Method Details

    • getName

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

    • addStepHandler

      void addStepHandler(FieldStepHandler<T> 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

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

    • clearStepHandlers

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

    • addEventHandler

      void addEventHandler(FieldEventHandler<T> handler, double maxCheckInterval, double convergence, int maxIterationCount)
      Add an event handler to the integrator.

      The default solver is a 5th order FieldBracketingNthOrderBrentSolver.

      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:

    • addEventHandler

      void addEventHandler(FieldEventHandler<T> handler, double maxCheckInterval, double convergence, int maxIterationCount, BracketedRealFieldUnivariateSolver<T> solver)
      Add an event handler to the integrator.
      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:

    • getEventHandlers

      Collection<FieldEventHandler<T>> getEventHandlers()
      Get all the event handlers that have been added to the integrator.
      Returns:
      an unmodifiable collection of the added events handlers
      See Also:

    • clearEventHandlers

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

    • getCurrentStepStart

      FieldODEStateAndDerivative<T> getCurrentStepStart()
      Get the current value of the step start time ti.

      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 state at step start time ti

    • getCurrentSignedStepsize

      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.

      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

      FieldODEStateAndDerivative<T> integrate(FieldExpandableODE<T> equations, FieldODEState<T> initialState, T finalTime) throws NumberIsTooSmallException, MaxCountExceededException, NoBracketingException
      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 thread-safe.

      Parameters:
      equations - differential equations to integrate
      initialState - 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)
      Returns:
      final state, its time will be the same as finalTime if integration reached its target, but may be different if some FieldEventHandler stops it at some point.
      Throws:
      NumberIsTooSmallException - if integration step is too small
      MaxCountExceededException - if the number of functions evaluations is exceeded
      NoBracketingException - if the location of an event cannot be bracketed