agi.foundation.numericalmethods.advanced

(agi.foundation.core-2024r2.jar)

Class RungeKuttaAdaptiveStepIntegrator

java.lang.Object

agi.foundation.numericalmethods.NumericalIntegrator

agi.foundation.numericalmethods.advanced.AdaptiveNumericalIntegrator

agi.foundation.numericalmethods.advanced.RungeKuttaAdaptiveStepIntegrator

All Implemented Interfaces:

ICloneWithContext, IThreadAware

Direct Known Subclasses:

RungeKuttaCashKarp45Integrator, RungeKuttaFehlberg78Integrator, RungeKuttaVerner89Integrator

public abstract class RungeKuttaAdaptiveStepIntegrator
extends AdaptiveNumericalIntegrator

Defines a Runge-Kutta integrator which can adapt the size of its steps based on the integration error.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	RungeKuttaAdaptiveStepIntegrator(RungeKuttaAdaptiveStepIntegrator existingInstance, CopyContext context) Initializes a new instance as a copy of an existing instance.
protected	RungeKuttaAdaptiveStepIntegrator(RungeKuttaAlgorithm tableau) Initializes a new instance based on the given tableau.

Method Summary

Modifier and Type	Method and Description
protected RungeKuttaAlgorithm	getTableau() Gets the Butcher Tableau with the coefficients and weights to use to perform the RungeKutta integration.
void	initialize(double x, double[] y) Initialize the integrator's initial independent and dependent variables and reset the integration parameters.
void	reintegrate(double stepSize) Repeats the last integration of the differential equations.
protected void	setTableau(RungeKuttaAlgorithm value) Sets the Butcher Tableau with the coefficients and weights to use to perform the RungeKutta integration.

Methods inherited from class agi.foundation.numericalmethods.advanced.AdaptiveNumericalIntegrator

adaptStep, adjustStep, boundAndTruncateStepSize, getAdaptiveWeights, getCurrentStepSize, getIterations, getMaximumIterations, getMaximumStepSize, getMinimumStepSize, getStepDeflationExponent, getStepDeflationFactor, getStepInflationExponent, getStepInflationFactor, getStepSizeBehavior, getStepTruncationOrder, integrate, integrate, setAdaptiveWeights, setCurrentStepSize, setIterations, setMaximumIterations, setMaximumStepSize, setMinimumStepSize, setStepDeflationExponent, setStepDeflationFactor, setStepInflationExponent, setStepInflationFactor, setStepSizeBehavior, setStepTruncationOrder

Methods inherited from class agi.foundation.numericalmethods.NumericalIntegrator

clone, getDimension, getDirection, getFinalDependentVariableValues, getFinalIndependentVariableValue, getInitialDependentVariableValues, getInitialIndependentVariableValue, getInitialStepSize, getIsThreadSafe, getPreviousStepSize, getStepSizeInformation, getSystemOfEquations, setDirection, setFinalDependentVariableValues, setFinalIndependentVariableValue, setInitialDependentVariableValues, setInitialIndependentVariableValue, setInitialStepSize, setStepSizeInformation, setSystemOfEquations, startNextStep

Methods inherited from class java.lang.Object

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

Constructor Detail

RungeKuttaAdaptiveStepIntegrator

protected RungeKuttaAdaptiveStepIntegrator(RungeKuttaAlgorithm tableau)

Initializes a new instance based on the given tableau.

Parameters:

tableau - The Butcher Tableau containing the coefficients and weights for the algorithm.

RungeKuttaAdaptiveStepIntegrator

protected RungeKuttaAdaptiveStepIntegrator(@Nonnull
                                           RungeKuttaAdaptiveStepIntegrator existingInstance,
                                           @Nonnull
                                           CopyContext context)

Initializes a new instance as a copy of an existing instance.

See ICloneWithContext.clone(CopyContext) for more information about how to implement this constructor in a derived class.

Parameters:

existingInstance - The existing instance to copy.

context - A CopyContext that controls the depth of the copy.

Throws:

ArgumentNullException - Thrown when existingInstance or context is null.

Method Detail

getTableau

protected final RungeKuttaAlgorithm getTableau()

Gets the Butcher Tableau with the coefficients and weights to use to perform the RungeKutta integration.

setTableau

protected final void setTableau(RungeKuttaAlgorithm value)

Sets the Butcher Tableau with the coefficients and weights to use to perform the RungeKutta integration.

initialize

public void initialize(double x,
                       double[] y)

Initialize the integrator's initial independent and dependent variables and reset the integration parameters. This should be called by the user prior to performing the first integration step.

Overrides:

initialize in class AdaptiveNumericalIntegrator

Parameters:

x - The value of the initial independent variable.

y - The values for the initial dependent variables.

reintegrate

public void reintegrate(double stepSize)

Repeats the last integration of the differential equations.

When overriding this method, note that the CurrentStepSize (get) property should be unaffected by the stepSize parameter.

Specified by:

reintegrate in class NumericalIntegrator

Parameters:

stepSize - The increment made to the InitialIndependentVariableValue (get / set) to transition to the new FinalIndependentVariableValue (get / set).