Class GillFieldStepInterpolator<T extends RealFieldElement<T>>
java.lang.Object
org.apache.commons.math3.ode.sampling.AbstractFieldStepInterpolator<T>
org.apache.commons.math3.ode.nonstiff.RungeKuttaFieldStepInterpolator<T>
org.apache.commons.math3.ode.nonstiff.GillFieldStepInterpolator<T>
- Type Parameters:
T
- the type of the field elements
- All Implemented Interfaces:
FieldStepInterpolator<T>
class GillFieldStepInterpolator<T extends RealFieldElement<T>>
extends RungeKuttaFieldStepInterpolator<T>
This class implements a step interpolator for the Gill fourth
order Runge-Kutta integrator.
This interpolator allows to compute dense output inside the last step computed. The interpolation equation is consistent with the integration scheme :
- Using reference point at step start:
y(tn + θ h) = y (tn) + θ (h/6) [ (6 - 9 θ + 4 θ2) y'1 + ( 6 θ - 4 θ2) ((1-1/√2) y'2 + (1+1/√2)) y'3) + ( - 3 θ + 4 θ2) y'4 ] - Using reference point at step start:
y(tn + θ h) = y (tn + h) - (1 - θ) (h/6) [ (1 - 5 θ + 4 θ2) y'1 + (2 + 2 θ - 4 θ2) ((1-1/√2) y'2 + (1+1/√2)) y'3) + (1 + θ + 4 θ2) y'4 ]
- Since:
- 3.6
- See Also:
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Field Summary
Fields -
Constructor Summary
ConstructorsConstructorDescriptionGillFieldStepInterpolator
(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
Modifier and TypeMethodDescriptionprotected FieldODEStateAndDerivative
<T> computeInterpolatedStateAndDerivatives
(FieldEquationsMapper<T> mapper, T time, T theta, T thetaH, T oneMinusThetaH) Compute the state and derivatives at the interpolated time.protected GillFieldStepInterpolator
<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.Methods inherited from class org.apache.commons.math3.ode.nonstiff.RungeKuttaFieldStepInterpolator
create, currentStateLinearCombination, derivativeLinearCombination, previousStateLinearCombination
Methods inherited from class org.apache.commons.math3.ode.sampling.AbstractFieldStepInterpolator
getCurrentState, getGlobalCurrentState, getGlobalPreviousState, getInterpolatedState, getPreviousState, isForward, restrictStep
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Field Details
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one_minus_inv_sqrt_2
First Gill coefficient. -
one_plus_inv_sqrt_2
Second Gill coefficient.
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Constructor Details
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GillFieldStepInterpolator
GillFieldStepInterpolator(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 belongforward
- integration direction indicatoryDotK
- slopes at the intermediate pointsglobalPreviousState
- start of the global stepglobalCurrentState
- end of the global stepsoftPreviousState
- start of the restricted stepsoftCurrentState
- end of the restricted stepmapper
- equations mapper for the all equations
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Method Details
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create
protected GillFieldStepInterpolator<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.- Specified by:
create
in classRungeKuttaFieldStepInterpolator<T extends RealFieldElement<T>>
- Parameters:
newField
- field to which the time and state vector elements belongnewForward
- integration direction indicatornewYDotK
- slopes at the intermediate pointsnewGlobalPreviousState
- start of the global stepnewGlobalCurrentState
- end of the global stepnewSoftPreviousState
- start of the restricted stepnewSoftCurrentState
- end of the restricted stepnewMapper
- equations mapper for the all equations- Returns:
- a new instance
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computeInterpolatedStateAndDerivatives
protected FieldODEStateAndDerivative<T> computeInterpolatedStateAndDerivatives(FieldEquationsMapper<T> mapper, T time, T theta, T thetaH, T oneMinusThetaH) Compute the state and derivatives at the interpolated time. This is the main processing method that should be implemented by the derived classes to perform the interpolation.- Specified by:
computeInterpolatedStateAndDerivatives
in classAbstractFieldStepInterpolator<T extends RealFieldElement<T>>
- Parameters:
mapper
- mapper for ODE equations primary and secondary componentstime
- interpolation timetheta
- normalized interpolation abscissa within the step (theta is zero at the previous time step and one at the current time step)thetaH
- time gap between the previous time and the interpolated timeoneMinusThetaH
- time gap between the interpolated time and the current time- Returns:
- interpolated state and derivatives
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