Top Description Fields Constructors Methods
org.apache.commons.math3.ode.nonstiff

public Class DormandPrince54FieldIntegrator<T extends RealFieldElement<T>>

extends EmbeddedRungeKuttaFieldIntegrator<T extends RealFieldElement<T>>
Class Inheritance
Type Parameters
<T>
the type of the field elements
Imports
org.apache.commons.math3.Field, .RealFieldElement, org.apache.commons.math3.ode.FieldEquationsMapper, .FieldODEStateAndDerivative, org.apache.commons.math3.util.MathArrays, .MathUtils

This class implements the 5(4) Dormand-Prince integrator for Ordinary Differential Equations.

This integrator is an embedded Runge-Kutta integrator of order 5(4) used in local extrapolation mode (i.e. the solution is computed using the high order formula) with stepsize control (and automatic step initialization) and continuous output. This method uses 7 functions evaluations per step. However, since this is an fsal, the last evaluation of one step is the same as the first evaluation of the next step and hence can be avoided. So the cost is really 6 functions evaluations per step.

This method has been published (whithout the continuous output that was added by Shampine in 1986) in the following article :

 A family of embedded Runge-Kutta formulae
 J. R. Dormand and P. J. Prince
 Journal of Computational and Applied Mathematics
 volume 6, no 1, 1980, pp. 19-26

Since
3.6

Field Summary

Modifier and TypeField and Description
private final T
e1

Error array, element 1.

private final T
e3

Error array, element 3.

private final T
e4

Error array, element 4.

private final T
e5

Error array, element 5.

private final T
e6

Error array, element 6.

private final T
e7

Error array, element 7.

private static final String
METHOD_NAME

Integrator method name.

Constructor Summary

AccessConstructor and Description
public
DormandPrince54FieldIntegrator(final Field<T>
field to which the time and state vector elements belong
field
,
final double
minimal step (sign is irrelevant, regardless of integration direction, forward or backward), the last step can be smaller than this
minStep
,
final double
maximal step (sign is irrelevant, regardless of integration direction, forward or backward), the last step can be smaller than this
maxStep
,
final double
allowed absolute error
scalAbsoluteTolerance
,
final double
allowed relative error
scalRelativeTolerance
)

Simple constructor.

public
DormandPrince54FieldIntegrator(final Field<T>
field to which the time and state vector elements belong
field
,
final double
minimal step (sign is irrelevant, regardless of integration direction, forward or backward), the last step can be smaller than this
minStep
,
final double
maximal step (sign is irrelevant, regardless of integration direction, forward or backward), the last step can be smaller than this
maxStep
,
final double[]
allowed absolute error
vecAbsoluteTolerance
,
final double[]
allowed relative error
vecRelativeTolerance
)

Simple constructor.

Method Summary

Modifier and TypeMethod and Description
protected DormandPrince54FieldStepInterpolator<T>
createInterpolator(final boolean
integration direction indicator
forward
,
T[][]
slopes at the intermediate points
yDotK
,
final FieldODEStateAndDerivative<T>
start of the global step
globalPreviousState
,
final FieldODEStateAndDerivative<T>
end of the global step
globalCurrentState
,
final FieldEquationsMapper<T>
equations mapper for the all equations
mapper
)

Implements abstract org.apache.commons.math3.ode.nonstiff.EmbeddedRungeKuttaFieldIntegrator.createInterpolator.

Create an interpolator.

protected T
estimateError(final T[][]
derivatives computed during the first stages
yDotK
,
final T[]
estimate of the step at the start of the step
y0
,
final T[]
estimate of the step at the end of the step
y1
,
final T
current step
h
)

Implements abstract org.apache.commons.math3.ode.nonstiff.EmbeddedRungeKuttaFieldIntegrator.estimateError.

Compute the error ratio.

public T[][]
getA()

Implements org.apache.commons.math3.ode.nonstiff.FieldButcherArrayProvider.getA.

Get the internal weights from Butcher array (without the first empty row).

public T[]
getB()

Implements org.apache.commons.math3.ode.nonstiff.FieldButcherArrayProvider.getB.

Get the external weights for the high order method from Butcher array.

public T[]
getC()

Implements org.apache.commons.math3.ode.nonstiff.FieldButcherArrayProvider.getC.

Get the time steps from Butcher array (without the first zero).

public int
Inherited from org.apache.commons.math3.ode.nonstiff.EmbeddedRungeKuttaFieldIntegrator:
fractionfractiongetMaxGrowthgetMinReductiongetSafetyintegratesetMaxGrowthsetMinReductionsetSafety

Field Detail

e1back to summary
private final T e1

Error array, element 1.

e3back to summary
private final T e3

Error array, element 3.

e4back to summary
private final T e4

Error array, element 4.

e5back to summary
private final T e5

Error array, element 5.

e6back to summary
private final T e6

Error array, element 6.

e7back to summary
private final T e7

Error array, element 7.

METHOD_NAMEback to summary
private static final String METHOD_NAME

Integrator method name.

Constructor Detail

DormandPrince54FieldIntegratorback to summary
public DormandPrince54FieldIntegrator(final Field<T> field, final double minStep, final double maxStep, final double scalAbsoluteTolerance, final double scalRelativeTolerance)

Simple constructor. Build a fifth order Dormand-Prince integrator with the given step bounds

Parameters
field:Field<T>

field to which the time and state vector elements belong

minStep:double

minimal step (sign is irrelevant, regardless of integration direction, forward or backward), the last step can be smaller than this

maxStep:double

maximal step (sign is irrelevant, regardless of integration direction, forward or backward), the last step can be smaller than this

scalAbsoluteTolerance:double

allowed absolute error

scalRelativeTolerance:double

allowed relative error

DormandPrince54FieldIntegratorback to summary
public DormandPrince54FieldIntegrator(final Field<T> field, final double minStep, final double maxStep, final double[] vecAbsoluteTolerance, final double[] vecRelativeTolerance)

Simple constructor. Build a fifth order Dormand-Prince integrator with the given step bounds

Parameters
field:Field<T>

field to which the time and state vector elements belong

minStep:double

minimal step (sign is irrelevant, regardless of integration direction, forward or backward), the last step can be smaller than this

maxStep:double

maximal step (sign is irrelevant, regardless of integration direction, forward or backward), the last step can be smaller than this

vecAbsoluteTolerance:double[]

allowed absolute error

vecRelativeTolerance:double[]

allowed relative error

Method Detail

createInterpolatorback to summary
protected DormandPrince54FieldStepInterpolator<T> createInterpolator(final boolean forward, T[][] yDotK, final FieldODEStateAndDerivative<T> globalPreviousState, final FieldODEStateAndDerivative<T> globalCurrentState, final FieldEquationsMapper<T> mapper)

Implements abstract org.apache.commons.math3.ode.nonstiff.EmbeddedRungeKuttaFieldIntegrator.createInterpolator.

Doc from org.apache.commons.math3.ode.nonstiff.EmbeddedRungeKuttaFieldIntegrator.createInterpolator.

Create an interpolator.

Parameters
forward:boolean

integration direction indicator

yDotK:T[][]

slopes at the intermediate points

globalPreviousState:FieldODEStateAndDerivative<T>

start of the global step

globalCurrentState:FieldODEStateAndDerivative<T>

end of the global step

mapper:FieldEquationsMapper<T>

equations mapper for the all equations

Returns:DormandPrince54FieldStepInterpolator<T>

external weights for the high order method from Butcher array

Annotations
@Override
estimateErrorback to summary
protected T estimateError(final T[][] yDotK, final T[] y0, final T[] y1, final T h)

Implements abstract org.apache.commons.math3.ode.nonstiff.EmbeddedRungeKuttaFieldIntegrator.estimateError.

Doc from org.apache.commons.math3.ode.nonstiff.EmbeddedRungeKuttaFieldIntegrator.estimateError.

Compute the error ratio.

Parameters
yDotK:T[][]

derivatives computed during the first stages

y0:T[]

estimate of the step at the start of the step

y1:T[]

estimate of the step at the end of the step

h:T

current step

Returns:T

error ratio, greater than 1 if step should be rejected

Annotations
@Override
getAback to summary
public T[][] getA()

Implements org.apache.commons.math3.ode.nonstiff.FieldButcherArrayProvider.getA.

Doc from org.apache.commons.math3.ode.nonstiff.FieldButcherArrayProvider.getA.

Get the internal weights from Butcher array (without the first empty row).

Returns:T[][]

internal weights from Butcher array (without the first empty row)

getBback to summary
public T[] getB()

Implements org.apache.commons.math3.ode.nonstiff.FieldButcherArrayProvider.getB.

Doc from org.apache.commons.math3.ode.nonstiff.FieldButcherArrayProvider.getB.

Get the external weights for the high order method from Butcher array.

Returns:T[]

external weights for the high order method from Butcher array

getCback to summary
public T[] getC()

Implements org.apache.commons.math3.ode.nonstiff.FieldButcherArrayProvider.getC.

Doc from org.apache.commons.math3.ode.nonstiff.FieldButcherArrayProvider.getC.

Get the time steps from Butcher array (without the first zero).

Returns:T[]

time steps from Butcher array (without the first zero

getOrderback to summary
public int getOrder()

Implements abstract org.apache.commons.math3.ode.nonstiff.EmbeddedRungeKuttaFieldIntegrator.getOrder.

Doc from org.apache.commons.math3.ode.nonstiff.EmbeddedRungeKuttaFieldIntegrator.getOrder.

Get the order of the method.

Returns:int

order of the method

Annotations
@Override