org.apache.commons.math3.ode.nonstiff

Class RungeKuttaFieldStepInterpolator<T extends RealFieldElement<T>>

java.lang.Object

org.apache.commons.math3.ode.sampling.AbstractFieldStepInterpolator<T>

org.apache.commons.math3.ode.nonstiff.RungeKuttaFieldStepInterpolator<T>

Type Parameters:

T - the type of the field elements

All Implemented Interfaces:

FieldStepInterpolator<T>

Direct Known Subclasses:

ClassicalRungeKuttaFieldStepInterpolator, DormandPrince54FieldStepInterpolator, DormandPrince853FieldStepInterpolator, EulerFieldStepInterpolator, GillFieldStepInterpolator, HighamHall54FieldStepInterpolator, LutherFieldStepInterpolator, MidpointFieldStepInterpolator, ThreeEighthesFieldStepInterpolator

abstract class RungeKuttaFieldStepInterpolator<T extends RealFieldElement<T>>
extends AbstractFieldStepInterpolator<T>

This class represents an interpolator over the last step during an ODE integration for Runge-Kutta and embedded Runge-Kutta integrators.

Since:

3.6

See Also:

RungeKuttaFieldIntegrator, EmbeddedRungeKuttaFieldIntegrator

Field Summary

Fields

Modifier and Type	Field and Description
private Field<T>	field Field to which the time and state vector elements belong.
private T[][]	yDotK Slopes at the intermediate points.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	RungeKuttaFieldStepInterpolator(Field<T> field, boolean forward, T[][] yDotK, FieldODEStateAndDerivative<T> globalPreviousState, FieldODEStateAndDerivative<T> globalCurrentState, FieldODEStateAndDerivative<T> softPreviousState, FieldODEStateAndDerivative<T> softCurrentState, FieldEquationsMapper<T> mapper) Simple constructor.

Method Summary

Methods

Modifier and Type	Method and Description
private T[]	combine(T[] a, T... coefficients) Linearly combine arrays.
protected RungeKuttaFieldStepInterpolator<T>	create(boolean newForward, FieldODEStateAndDerivative<T> newGlobalPreviousState, FieldODEStateAndDerivative<T> newGlobalCurrentState, FieldODEStateAndDerivative<T> newSoftPreviousState, FieldODEStateAndDerivative<T> newSoftCurrentState, FieldEquationsMapper<T> newMapper) Create a new instance.
protected abstract RungeKuttaFieldStepInterpolator<T>	create(Field<T> newField, boolean newForward, T[][] newYDotK, FieldODEStateAndDerivative<T> newGlobalPreviousState, FieldODEStateAndDerivative<T> newGlobalCurrentState, FieldODEStateAndDerivative<T> newSoftPreviousState, FieldODEStateAndDerivative<T> newSoftCurrentState, FieldEquationsMapper<T> newMapper) Create a new instance.
protected T[]	currentStateLinearCombination(T... coefficients) Compute a state by linear combination added to current state.
protected T[]	derivativeLinearCombination(T... coefficients) Compute a state derivative by linear combination.
protected T[]	previousStateLinearCombination(T... coefficients) Compute a state by linear combination added to previous state.

Methods inherited from class org.apache.commons.math3.ode.sampling.AbstractFieldStepInterpolator

computeInterpolatedStateAndDerivatives, getCurrentState, getGlobalCurrentState, getGlobalPreviousState, getInterpolatedState, getPreviousState, isForward, restrictStep

Methods inherited from class java.lang.Object

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

Field Detail

field

private final Field<T extends RealFieldElement<T>> field

Field to which the time and state vector elements belong.

yDotK

private final T extends RealFieldElement<T>[][] yDotK

Slopes at the intermediate points.

Constructor Detail

RungeKuttaFieldStepInterpolator

protected RungeKuttaFieldStepInterpolator(Field<T> field,
                               boolean forward,
                               T[][] yDotK,
                               FieldODEStateAndDerivative<T> globalPreviousState,
                               FieldODEStateAndDerivative<T> globalCurrentState,
                               FieldODEStateAndDerivative<T> softPreviousState,
                               FieldODEStateAndDerivative<T> softCurrentState,
                               FieldEquationsMapper<T> mapper)

Simple constructor.

Parameters:

field - field to which the time and state vector elements belong

forward - integration direction indicator

yDotK - slopes at the intermediate points

globalPreviousState - start of the global step

globalCurrentState - end of the global step

softPreviousState - start of the restricted step

softCurrentState - end of the restricted step

mapper - equations mapper for the all equations

Method Detail

create

protected RungeKuttaFieldStepInterpolator<T> create(boolean newForward,
                                        FieldODEStateAndDerivative<T> newGlobalPreviousState,
                                        FieldODEStateAndDerivative<T> newGlobalCurrentState,
                                        FieldODEStateAndDerivative<T> newSoftPreviousState,
                                        FieldODEStateAndDerivative<T> newSoftCurrentState,
                                        FieldEquationsMapper<T> newMapper)

Create a new instance.

Specified by:

create in class AbstractFieldStepInterpolator<T extends RealFieldElement<T>>

Parameters:

newForward - integration direction indicator

newGlobalPreviousState - start of the global step

newGlobalCurrentState - end of the global step

newSoftPreviousState - start of the restricted step

newSoftCurrentState - end of the restricted step

newMapper - equations mapper for the all equations

Returns:

a new instance

create

protected abstract RungeKuttaFieldStepInterpolator<T> create(Field<T> newField,
                                        boolean newForward,
                                        T[][] newYDotK,
                                        FieldODEStateAndDerivative<T> newGlobalPreviousState,
                                        FieldODEStateAndDerivative<T> newGlobalCurrentState,
                                        FieldODEStateAndDerivative<T> newSoftPreviousState,
                                        FieldODEStateAndDerivative<T> newSoftCurrentState,
                                        FieldEquationsMapper<T> newMapper)

Create a new instance.

Parameters:

newField - field to which the time and state vector elements belong

newForward - integration direction indicator

newYDotK - slopes at the intermediate points

newGlobalPreviousState - start of the global step

newGlobalCurrentState - end of the global step

newSoftPreviousState - start of the restricted step

newSoftCurrentState - end of the restricted step

newMapper - equations mapper for the all equations

Returns:

a new instance

previousStateLinearCombination

protected final T[] previousStateLinearCombination(T... coefficients)

Compute a state by linear combination added to previous state.

Parameters:

coefficients - coefficients to apply to the method staged derivatives

Returns:

combined state

currentStateLinearCombination

protected T[] currentStateLinearCombination(T... coefficients)

Compute a state by linear combination added to current state.

Parameters:

coefficients - coefficients to apply to the method staged derivatives

Returns:

combined state

derivativeLinearCombination

protected T[] derivativeLinearCombination(T... coefficients)

Compute a state derivative by linear combination.

Parameters:

coefficients - coefficients to apply to the method staged derivatives

Returns:

combined state

combine

private T[] combine(T[] a,
          T... coefficients)

Linearly combine arrays.

Parameters:

a - array to add to

coefficients - coefficients to apply to the method staged derivatives

Returns:

a itself, as a convenience for fluent API