Interface ExplicitRungeKuttaIntegrator
- All Superinterfaces:
ButcherArrayProvider
,ODEIntegrator
- All Known Implementing Classes:
ClassicalRungeKuttaIntegrator
,DormandPrince54Integrator
,DormandPrince853Integrator
,EmbeddedRungeKuttaIntegrator
,EulerIntegrator
,GillIntegrator
,HighamHall54Integrator
,LutherIntegrator
,MidpointIntegrator
,RungeKuttaIntegrator
,ThreeEighthesIntegrator
These methods are explicit Runge-Kutta methods, their Butcher arrays are as follows :
0 | c2 | a21 c3 | a31 a32 ... | ... cs | as1 as2 ... ass-1 |-------------------------- | b1 b2 ... bs-1 bs
- Since:
- 3.1
- See Also:
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Method Summary
Modifier and TypeMethodDescriptionstatic double[]
applyExternalButcherWeights
(double[] y0, double[][] yDotK, double h, double[] b) Apply external weights of Butcher array, assuming internal ones have been applied.static void
applyInternalButcherWeights
(ExpandableODE equations, double t0, double[] y0, double h, double[][] a, double[] c, double[][] yDotK) Apply internal weights of Butcher array, with corresponding times.default int
Getter for the number of stages corresponding to the Butcher array.default double[]
singleStep
(OrdinaryDifferentialEquation equations, double t0, double[] y0, double t) Fast computation of a single step of ODE integration.Methods inherited from interface org.hipparchus.ode.nonstiff.ButcherArrayProvider
getA, getB, getC
Methods inherited from interface org.hipparchus.ode.ODEIntegrator
addEventDetector, addStepEndHandler, addStepHandler, clearEventDetectors, clearStepEndHandlers, clearStepHandlers, getCurrentSignedStepsize, getEvaluations, getEventDetectors, getMaxEvaluations, getName, getStepEndHandlers, getStepHandlers, getStepStart, integrate, integrate, setMaxEvaluations
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Method Details
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getNumberOfStages
default int getNumberOfStages()Getter for the number of stages corresponding to the Butcher array.- Returns:
- number of stages
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singleStep
default double[] singleStep(OrdinaryDifferentialEquation equations, double t0, double[] y0, double t) Fast computation of a single step of ODE integration.This method is intended for the limited use case of very fast computation of only one step without using any of the rich features of general integrators that may take some time to set up (i.e. no step handlers, no events handlers, no additional states, no interpolators, no error control, no evaluations count, no sanity checks ...). It handles the strict minimum of computation, so it can be embedded in outer loops.
This method is not used at all by the
ODEIntegrator.integrate(ExpandableODE, ODEState, double)
method. It also completely ignores the step set at construction time, and uses only a single step to go fromt0
tot
.As this method does not use any of the state-dependent features of the integrator, it should be reasonably thread-safe if and only if the provided differential equations are themselves thread-safe.
- Parameters:
equations
- differential equations to integratet0
- initial timey0
- initial value of the state vector at t0t
- target time for the integration (can be set to a value smaller thant0
for backward integration)- Returns:
- state vector at
t
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applyInternalButcherWeights
static void applyInternalButcherWeights(ExpandableODE equations, double t0, double[] y0, double h, double[][] a, double[] c, double[][] yDotK) Apply internal weights of Butcher array, with corresponding times.- Parameters:
equations
- differential equations to integratet0
- initial timey0
- initial value of the state vector at t0h
- step sizea
- internal weights of Butcher arrayc
- times of Butcher arrayyDotK
- array where to store result
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applyExternalButcherWeights
static double[] applyExternalButcherWeights(double[] y0, double[][] yDotK, double h, double[] b) Apply external weights of Butcher array, assuming internal ones have been applied.- Parameters:
yDotK
- output of stagesy0
- initial value of the state vector at t0h
- step sizeb
- external weights of Butcher array- Returns:
- state vector
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