Package org.hipparchus.ode.nonstiff
Class LutherFieldIntegrator<T extends CalculusFieldElement<T>>
java.lang.Object
org.hipparchus.ode.AbstractFieldIntegrator<T>
org.hipparchus.ode.nonstiff.RungeKuttaFieldIntegrator<T>
org.hipparchus.ode.nonstiff.LutherFieldIntegrator<T>
- Type Parameters:
T
- the type of the field elements
- All Implemented Interfaces:
FieldODEIntegrator<T>
,FieldButcherArrayProvider<T>
,FieldExplicitRungeKuttaIntegrator<T>
public class LutherFieldIntegrator<T extends CalculusFieldElement<T>>
extends RungeKuttaFieldIntegrator<T>
This class implements the Luther sixth order Runge-Kutta
integrator for Ordinary Differential Equations.
This method is described in H. A. Luther 1968 paper An explicit Sixth-Order Runge-Kutta Formula.
This method is an explicit Runge-Kutta method, its Butcher-array is the following one :
0 | 0 0 0 0 0 0 1 | 1 0 0 0 0 0 1/2 | 3/8 1/8 0 0 0 0 2/3 | 8/27 2/27 8/27 0 0 0 (7-q)/14 | ( -21 + 9q)/392 ( -56 + 8q)/392 ( 336 - 48q)/392 ( -63 + 3q)/392 0 0 (7+q)/14 | (-1155 - 255q)/1960 ( -280 - 40q)/1960 ( 0 - 320q)/1960 ( 63 + 363q)/1960 ( 2352 + 392q)/1960 0 1 | ( 330 + 105q)/180 ( 120 + 0q)/180 ( -200 + 280q)/180 ( 126 - 189q)/180 ( -686 - 126q)/180 ( 490 - 70q)/180 |-------------------------------------------------------------------------------------------------------------------------------------------------- | 1/20 0 16/45 0 49/180 49/180 1/20
where q = √21
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Field Summary
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Constructor Summary
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Method Summary
Modifier and TypeMethodDescriptionprotected org.hipparchus.ode.nonstiff.LutherFieldStateInterpolator<T>
createInterpolator
(boolean forward, T[][] yDotK, FieldODEStateAndDerivative<T> globalPreviousState, FieldODEStateAndDerivative<T> globalCurrentState, FieldEquationsMapper<T> mapper) Create an interpolator.T[][]
getA()
Get the internal weights from Butcher array (without the first empty row).T[]
getB()
Get the external weights for the high order method from Butcher array.T[]
getC()
Get the time steps from Butcher array (without the first zero).Methods inherited from class org.hipparchus.ode.nonstiff.RungeKuttaFieldIntegrator
getDefaultStep, getNumberOfStages, initIntegration, integrate, isUsingFieldCoefficients, setUsingFieldCoefficients
Methods inherited from class org.hipparchus.ode.AbstractFieldIntegrator
acceptStep, addEventDetector, addStepEndHandler, addStepHandler, clearEventDetectors, clearStepEndHandlers, clearStepHandlers, computeDerivatives, getCurrentSignedStepsize, getEquations, getEvaluations, getEvaluationsCounter, getEventDetectors, getField, getMaxEvaluations, getName, getStepEndHandlers, getStepHandlers, getStepSize, getStepStart, incrementEvaluations, isLastStep, resetOccurred, sanityChecks, setIsLastStep, setMaxEvaluations, setStateInitialized, setStepSize, setStepStart
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
Methods inherited from interface org.hipparchus.ode.nonstiff.FieldExplicitRungeKuttaIntegrator
getRealA, getRealB, getRealC, singleStep
Methods inherited from interface org.hipparchus.ode.FieldODEIntegrator
addEventDetector, addStepEndHandler, addStepHandler, clearEventDetectors, clearStepEndHandlers, clearStepHandlers, getCurrentSignedStepsize, getEvaluations, getEventDetectors, getMaxEvaluations, getName, getStepEndHandlers, getStepHandlers, getStepStart, setMaxEvaluations
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Field Details
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METHOD_NAME
Name of integration scheme.- See Also:
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Constructor Details
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LutherFieldIntegrator
Simple constructor. Build a fourth-order Luther integrator with the given step.- Parameters:
field
- field to which the time and state vector elements belongstep
- integration step
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Method Details
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getC
Get the time steps from Butcher array (without the first zero).- Returns:
- time steps from Butcher array (without the first zero
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getA
Get the internal weights from Butcher array (without the first empty row).- Returns:
- internal weights from Butcher array (without the first empty row)
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getB
Get the external weights for the high order method from Butcher array.- Returns:
- external weights for the high order method from Butcher array
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createInterpolator
protected org.hipparchus.ode.nonstiff.LutherFieldStateInterpolator<T> createInterpolator(boolean forward, T[][] yDotK, FieldODEStateAndDerivative<T> globalPreviousState, FieldODEStateAndDerivative<T> globalCurrentState, FieldEquationsMapper<T> mapper) Create an interpolator.- Specified by:
createInterpolator
in classRungeKuttaFieldIntegrator<T extends CalculusFieldElement<T>>
- Parameters:
forward
- integration direction indicatoryDotK
- slopes at the intermediate pointsglobalPreviousState
- start of the global stepglobalCurrentState
- end of the global stepmapper
- equations mapper for the all equations- Returns:
- external weights for the high order method from Butcher array
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