fr.cnes.sirius.patrius.orbits.pvcoordinates

Class AbstractEphemerisPvHermiteLagrange

java.lang.Object

fr.cnes.sirius.patrius.orbits.pvcoordinates.AbstractBoundedPVProvider

fr.cnes.sirius.patrius.orbits.pvcoordinates.AbstractEphemerisPvHermiteLagrange

All Implemented Interfaces:

PVCoordinatesProvider, Serializable

Direct Known Subclasses:

EphemerisPvHermite, EphemerisPvLagrange

public abstract class AbstractEphemerisPvHermiteLagrange
extends AbstractBoundedPVProvider

Abstract class defining common methods and elements for an interpolation of an ephemeris PV via Lagrange-Hermite methods.

Author:

Nicola NATALE, Manuel AMOUROUX

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
protected HermiteInterpolator	interpolator Ephemeris Hermite interpolator

Fields inherited from class fr.cnes.sirius.patrius.orbits.pvcoordinates.AbstractBoundedPVProvider

polyOrder, tDate, tPVCoord

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	AbstractEphemerisPvHermiteLagrange(PVCoordinates[] tabPV, int order, Frame frame, AbsoluteDate[] tabDate, ISearchIndex algo) Instantiation of AbstractEphemerisPvHermiteLagrange attributes.
protected	AbstractEphemerisPvHermiteLagrange(SpacecraftState[] tabState, int order, ISearchIndex algo) Creates an instance of AbstractEphemerisPvHermiteLagrange from a SpacecraftState table.

Method Summary

Modifier and Type	Method and Description
protected PVCoordinates	getPVCoordinates(AbsoluteDate date, Frame frame, Vector3D[] tAcc, boolean velocityAsDerivative) Common method to get PV coordinates using Hermite interpolation, either in a "Lagrange-like" manner, or in a traditional manner.

Methods inherited from class fr.cnes.sirius.patrius.orbits.pvcoordinates.AbstractBoundedPVProvider

checkBounds, getDateRef, getFrame, getMaxDate, getMinDate, getNativeFrame, getPreviousIndex, getSearchIndex, indexValidity, setPreviousIndex

Methods inherited from class java.lang.Object

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

Methods inherited from interface fr.cnes.sirius.patrius.orbits.pvcoordinates.PVCoordinatesProvider

getPVCoordinates

Field Detail

interpolator

protected HermiteInterpolator interpolator

Ephemeris Hermite interpolator

Constructor Detail

AbstractEphemerisPvHermiteLagrange

protected AbstractEphemerisPvHermiteLagrange(PVCoordinates[] tabPV,
                                             int order,
                                             Frame frame,
                                             AbsoluteDate[] tabDate,
                                             ISearchIndex algo)

Instantiation of AbstractEphemerisPvHermiteLagrange attributes.
Only used by children classes.

Parameters:

tabPV - position velocity coordinates table (table is not copied and so internal class state can be modified from outside)

order - Lagrange/Hermite interpolation order. It must be even.

frame - coordinates expression frame

tabDate - table of dates for each position velocity (table is not copied and so internal class state can be modified from outside)

algo - class to find the nearest date index from a given date in the date table (If null, algo will be, by default, a BinarySearchIndexOpenClosed based on a table of duration since the first date of the dates table)

AbstractEphemerisPvHermiteLagrange

protected AbstractEphemerisPvHermiteLagrange(SpacecraftState[] tabState,
                                             int order,
                                             ISearchIndex algo)

Creates an instance of AbstractEphemerisPvHermiteLagrange from a SpacecraftState table.
Only used by children classes.

Parameters:

tabState - SpacecraftState table

order - Lagrange/Hermite interpolation order. It must be even.

algo - class to find the nearest date index from a given date (If null, algo will be BinarySearchIndexOpenClosed by default based on a table of duration since the first date of the dates table)

Method Detail

getPVCoordinates

protected PVCoordinates getPVCoordinates(AbsoluteDate date,
                                         Frame frame,
                                         Vector3D[] tAcc,
                                         boolean velocityAsDerivative)
                                  throws PatriusException

Common method to get PV coordinates using Hermite interpolation, either in a "Lagrange-like" manner, or in a traditional manner.
The "Lagrange-like" manner uses a Hermite interpolation, without acceleration, and considers the velocities as additional mesh dimensions, not derivatives. We therefore interpolate a 6D vector, without derivatives. Using this interpolation rather than the traditional Lagrange one improves significantly the speed, with numerical errors considered acceptable.
The traditional manner uses a Hermite interpolation, with velocities vector as derivatives, and optional accelerations as second order derivatives.

Parameters:

date - date of interpolation

frame - frame of coordinates expression. (can be null)

tAcc - date of interpolation

velocityAsDerivative - The velocities are considered as additional mesh dimensions (Lagrange-like interpolation) when true, as derivatives when false

Returns:

PVcoordinates at interpolation date in the chosen frame

Throws:

PatriusException - if date of interpolation is too near from min and max input dates compare to Lagrange order