Package org.orekit.time

Class AbstractTimeInterpolator<T extends TimeStamped>

java.lang.Object

org.orekit.time.AbstractTimeInterpolator<T>

Type Parameters:

T - interpolated time stamped type

All Implemented Interfaces:

TimeInterpolator<T>

Direct Known Subclasses:

AbsolutePVCoordinatesHermiteInterpolator, AbstractOrbitInterpolator, AbstractStateCovarianceInterpolator, AttitudeInterpolator, ClockOffsetHermiteInterpolator, SP3CoordinateHermiteInterpolator, SpacecraftStateInterpolator, TimeStampedAngularCoordinatesHermiteInterpolator, TimeStampedDoubleAndDerivativeHermiteInterpolator, TimeStampedDoubleHermiteInterpolator, TimeStampedPVCoordinatesHermiteInterpolator

public abstract class AbstractTimeInterpolator<T extends TimeStamped>
extends Object
implements TimeInterpolator<T>

Abstract class for time interpolator.

Author:

Vincent Cucchietti

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
class	AbstractTimeInterpolator.InterpolationData	Nested class used to store interpolation data.

Field Summary

Fields

Modifier and Type	Field	Description
static double	DEFAULT_EXTRAPOLATION_THRESHOLD_SEC	Default extrapolation time threshold: 1ms.
static int	DEFAULT_INTERPOLATION_POINTS	Default number of interpolation points.

Constructor Summary

Constructors

Constructor	Description
AbstractTimeInterpolator(int interpolationPoints, double extrapolationThreshold)	Constructor.

Method Summary

Modifier and Type	Method	Description
protected void	addOptionalSubInterpolatorIfDefined(TimeInterpolator<? extends TimeStamped> subInterpolator, List<TimeInterpolator<? extends TimeStamped>> subInterpolators)	Add all lowest level sub interpolators to the sub interpolator list.
static void	checkInterpolatorCompatibilityWithSampleSize(TimeInterpolator<? extends TimeStamped> interpolator, int sampleSize)	Method checking if given interpolator is compatible with given sample size.
static AbsoluteDate	getCentralDate(AbsoluteDate date, AbsoluteDate minDate, AbsoluteDate maxDate, double threshold)	Get the central date to use to find neighbors while taking into account an extrapolation threshold.
static <T extends TimeStamped> AbsoluteDate	getCentralDate(AbsoluteDate date, ImmutableTimeStampedCache<T> cachedSamples, double threshold)	Get the central date to use to find neighbors while taking into account extrapolation threshold.
double	getExtrapolationThreshold()	Get the extrapolation threshold.
int	getInternalNbInterpolationPoints()	Get the number of interpolation points for this instance only i.e., not taking into account sub-interpolators.
int	getNbInterpolationPoints()	Get the number of interpolation points.
List<TimeInterpolator<? extends TimeStamped>>	getSubInterpolators()	Get all lowest level interpolators implemented by this instance, otherwise return a list with this instance only.
protected double	getTimeParameter(AbsoluteDate interpolatingTime, AbsoluteDate previousDate, AbsoluteDate nextDate)	Get the time parameter which lies between [0:1] by normalizing the difference between interpolating time and previous date by the Δt between tabulated values.
T	interpolate(AbsoluteDate interpolationDate, Collection<T> sample)	Get an interpolated instance.
T	interpolate(AbsoluteDate interpolationDate, Stream<T> sample)	Get an interpolated instance.
protected abstract T	interpolate(AbstractTimeInterpolator.InterpolationData interpolationData)	Interpolate instance from given interpolation data.

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_EXTRAPOLATION_THRESHOLD_SEC

public static final double DEFAULT_EXTRAPOLATION_THRESHOLD_SEC

Default extrapolation time threshold: 1ms.

See Also:

Constant Field Values

DEFAULT_INTERPOLATION_POINTS

public static final int DEFAULT_INTERPOLATION_POINTS

Default number of interpolation points.

See Also:

Constant Field Values

Constructor Detail

AbstractTimeInterpolator

public AbstractTimeInterpolator(int interpolationPoints,
                                double extrapolationThreshold)

Constructor.

Parameters:

interpolationPoints - number of interpolation points

extrapolationThreshold - extrapolation threshold beyond which the propagation will fail

Method Detail

checkInterpolatorCompatibilityWithSampleSize

public static void checkInterpolatorCompatibilityWithSampleSize(TimeInterpolator<? extends TimeStamped> interpolator,
                                                                int sampleSize)

Method checking if given interpolator is compatible with given sample size.

Parameters:

interpolator - interpolator

sampleSize - sample size

interpolate

public T interpolate(AbsoluteDate interpolationDate,
                     Stream<T> sample)

Get an interpolated instance.

The stream must yield elements in chronological order. Passing an unsorted stream yields undefined neighbors and may throw TimeStampedCacheException.

The stream must hold elements in chronological order.

Specified by:

interpolate in interface TimeInterpolator<T extends TimeStamped>

Parameters:

interpolationDate - interpolation date

sample - time stamped sample (chronologically sorted)

Returns:

a new instance, interpolated at specified date

See Also:

TimeStamped, AbsoluteDate

interpolate

public T interpolate(AbsoluteDate interpolationDate,
                     Collection<T> sample)

Get an interpolated instance.

The sample must be in chronological order. Passing an unsorted sample yields undefined neighbors and may throw TimeStampedCacheException.

Precondition: sample must be sorted in chronological order. Passing an unsorted sample yields undefined neighbors and may throw TimeStampedCacheException.

Specified by:

interpolate in interface TimeInterpolator<T extends TimeStamped>

Parameters:

interpolationDate - interpolation date

sample - time stamped sample (chronologically sorted)

Returns:

a new instance, interpolated at specified date

getCentralDate

public static <T extends TimeStamped> AbsoluteDate getCentralDate(AbsoluteDate date,
                                                                  ImmutableTimeStampedCache<T> cachedSamples,
                                                                  double threshold)

Get the central date to use to find neighbors while taking into account extrapolation threshold.

Type Parameters:

T - type of element

Parameters:

date - interpolation date

cachedSamples - cached samples

threshold - extrapolation threshold

Returns:

central date to use to find neighbors

Since:

12.0.1

getCentralDate

public static AbsoluteDate getCentralDate(AbsoluteDate date,
                                          AbsoluteDate minDate,
                                          AbsoluteDate maxDate,
                                          double threshold)

Get the central date to use to find neighbors while taking into account an extrapolation threshold.

Parameters:

date - interpolation date

minDate - earliest date in the sample.

maxDate - latest date in the sample.

threshold - extrapolation threshold

Returns:

central date to use to find neighbors

Since:

12.0.1

getSubInterpolators

public List<TimeInterpolator<? extends TimeStamped>> getSubInterpolators()

Get all lowest level interpolators implemented by this instance, otherwise return a list with this instance only.

An example would be the spacecraft state interpolator which can use different interpolators for each of its attributes (orbit, absolute position-velocity-acceleration coordinates, mass...). In this case, it would return the list of all of these interpolators (or possibly all of their sub-interpolators if they were to use multiple interpolators themselves).

Specified by:

getSubInterpolators in interface TimeInterpolator<T extends TimeStamped>

Returns:

list of interpolators

getNbInterpolationPoints

public int getNbInterpolationPoints()

Get the number of interpolation points. In the specific case where this interpolator contains multiple sub-interpolators, this method will return the maximum number of interpolation points required among all sub-interpolators.

Specified by:

getNbInterpolationPoints in interface TimeInterpolator<T extends TimeStamped>

Returns:

the number of interpolation points

getInternalNbInterpolationPoints

public int getInternalNbInterpolationPoints()

Get the number of interpolation points for this instance only i.e., not taking into account sub-interpolators.

Returns:

required the number of interpolation points for this instance only i.e., not taking into account sub-interpolators.

getExtrapolationThreshold

public double getExtrapolationThreshold()

Get the extrapolation threshold.

Specified by:

getExtrapolationThreshold in interface TimeInterpolator<T extends TimeStamped>

Returns:

get the extrapolation threshold

addOptionalSubInterpolatorIfDefined

protected void addOptionalSubInterpolatorIfDefined(TimeInterpolator<? extends TimeStamped> subInterpolator,
                                                   List<TimeInterpolator<? extends TimeStamped>> subInterpolators)

Add all lowest level sub interpolators to the sub interpolator list.

Parameters:

subInterpolator - optional sub interpolator to add

subInterpolators - list of sub interpolators

interpolate

protected abstract T interpolate(AbstractTimeInterpolator.InterpolationData interpolationData)

Interpolate instance from given interpolation data.

Parameters:

interpolationData - interpolation data

Returns:

interpolated instance from given interpolation data.

getTimeParameter

protected double getTimeParameter(AbsoluteDate interpolatingTime,
                                  AbsoluteDate previousDate,
                                  AbsoluteDate nextDate)

Get the time parameter which lies between [0:1] by normalizing the difference between interpolating time and previous date by the Δt between tabulated values.

Parameters:

interpolatingTime - time at which we want to interpolate a value (between previous and next tabulated dates)

previousDate - previous tabulated value date

nextDate - next tabulated value date

Returns:

time parameter which lies between [0:1]