org.orekit.propagation.integration

Class IntegratedEphemeris

java.lang.Object

org.orekit.propagation.AbstractPropagator

org.orekit.propagation.analytical.AbstractAnalyticalPropagator

org.orekit.propagation.integration.IntegratedEphemeris

All Implemented Interfaces:

Serializable, BoundedPropagator, Propagator, PVCoordinatesProvider

public class IntegratedEphemeris
extends AbstractAnalyticalPropagator
implements BoundedPropagator, Serializable

This class stores sequentially generated orbital parameters for later retrieval.

Instances of this class are built and then must be fed with the results provided by Propagator objects configured in ephemeris generation mode. Once propagation is o, random access to any intermediate state of the orbit throughout the propagation range is possible.

A typical use case is for numerically integrated orbits, which can be used by algorithms that need to wander around according to their own algorithm without cumbersome tight links with the integrator.

Another use case is persistence, as this class is one of the few propagators to be serializable.

As this class implements the Propagator interface, it can itself be used in batch mode to build another instance of the same type. This is however not recommended since it would be a waste of resources.

Note that this class stores all intermediate states along with interpolation models, so it may be memory intensive.

Author:

Mathieu Roméro, Luc Maisonobe, Véronique Pommier-Maurussane

See Also:

NumericalPropagator, Serialized Form

Field Summary

Fields inherited from interface org.orekit.propagation.Propagator

DEFAULT_LAW, DEFAULT_MASS, EPHEMERIS_GENERATION_MODE, MASTER_MODE, SLAVE_MODE

Constructor Summary

Constructors

Constructor and Description
IntegratedEphemeris(AbsoluteDate startDate, AbsoluteDate minDate, AbsoluteDate maxDate, StateMapper mapper, boolean meanOrbit, DenseOutputModel model, Map<String,double[]> unmanaged, List<AdditionalStateProvider> providers, String[] equations) Creates a new instance of IntegratedEphemeris.

Method Summary

Modifier and Type	Method and Description
protected SpacecraftState	basicPropagate(AbsoluteDate date) Propagate an orbit without any fancy features.
Frame	getFrame() Get the frame in which the orbit is propagated.
SpacecraftState	getInitialState() Get the propagator initial state.
protected double	getMass(AbsoluteDate date) Get the mass.
AbsoluteDate	getMaxDate() Get the last date of the range.
AbsoluteDate	getMinDate() Get the first date of the range.
TimeStampedPVCoordinates	getPVCoordinates(AbsoluteDate date, Frame frame) Get the PVCoordinates of the body in the selected frame.
protected Orbit	propagateOrbit(AbsoluteDate date) Extrapolate an orbit up to a specific target date.
void	resetInitialState(SpacecraftState state) Reset the propagator initial state.
protected void	resetIntermediateState(SpacecraftState state, boolean forward) Reset an intermediate state.

Methods inherited from class org.orekit.propagation.analytical.AbstractAnalyticalPropagator

acceptStep, addEventDetector, clearEventsDetectors, getEventsDetectors, getGeneratedEphemeris, getPvProvider, propagate

Methods inherited from class org.orekit.propagation.AbstractPropagator

addAdditionalStateProvider, getAdditionalStateProviders, getAttitudeProvider, getFixedStepSize, getManagedAdditionalStates, getMode, getStartDate, getStepHandler, isAdditionalStateManaged, propagate, setAttitudeProvider, setEphemerisMode, setEphemerisMode, setMasterMode, setMasterMode, setSlaveMode, setStartDate, updateAdditionalStates

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.orekit.propagation.Propagator

addAdditionalStateProvider, addEventDetector, clearEventsDetectors, getAdditionalStateProviders, getAttitudeProvider, getEventsDetectors, getGeneratedEphemeris, getManagedAdditionalStates, getMode, isAdditionalStateManaged, propagate, propagate, setAttitudeProvider, setEphemerisMode, setEphemerisMode, setMasterMode, setMasterMode, setSlaveMode

Constructor Detail

IntegratedEphemeris

public IntegratedEphemeris(AbsoluteDate startDate,
                           AbsoluteDate minDate,
                           AbsoluteDate maxDate,
                           StateMapper mapper,
                           boolean meanOrbit,
                           DenseOutputModel model,
                           Map<String,double[]> unmanaged,
                           List<AdditionalStateProvider> providers,
                           String[] equations)
                    throws OrekitException

Creates a new instance of IntegratedEphemeris.

Parameters:

startDate - Start date of the integration (can be minDate or maxDate)

minDate - first date of the range

maxDate - last date of the range

mapper - mapper between raw double components and spacecraft state

meanOrbit - output only the mean orbit

model - underlying raw mathematical model

unmanaged - unmanaged additional states that must be simply copied

providers - providers for pre-integrated states

equations - names of additional equations

Throws:

OrekitException - if several providers have the same name

Method Detail

basicPropagate

protected SpacecraftState basicPropagate(AbsoluteDate date)
                                  throws OrekitException

Propagate an orbit without any fancy features.

This method is similar in spirit to the AbstractAnalyticalPropagator.propagate(org.orekit.time.AbsoluteDate, org.orekit.time.AbsoluteDate) method, except that it does not call any handler during propagation, nor any discrete events, not additional states. It always stop exactly at the specified date.

Overrides:

basicPropagate in class AbstractAnalyticalPropagator

Parameters:

date - target date for propagation

Returns:

state at specified date

Throws:

OrekitException - if propagation cannot reach specified date

propagateOrbit

protected Orbit propagateOrbit(AbsoluteDate date)
                        throws OrekitException

Extrapolate an orbit up to a specific target date.

Specified by:

propagateOrbit in class AbstractAnalyticalPropagator

Parameters:

date - target date for the orbit

Returns:

extrapolated parameters

Throws:

OrekitException - if some parameters are out of bounds

getMass

protected double getMass(AbsoluteDate date)
                  throws OrekitException

Get the mass.

Specified by:

getMass in class AbstractAnalyticalPropagator

Parameters:

date - target date for the orbit

Returns:

mass mass

Throws:

OrekitException - if some parameters are out of bounds

getPVCoordinates

public TimeStampedPVCoordinates getPVCoordinates(AbsoluteDate date,
                                                 Frame frame)
                                          throws OrekitException

Get the PVCoordinates of the body in the selected frame.

Specified by:

getPVCoordinates in interface PVCoordinatesProvider

Overrides:

getPVCoordinates in class AbstractPropagator

Parameters:

date - current date

frame - the frame where to define the position

Returns:

time-stamped position/velocity of the body (m and m/s)

Throws:

OrekitException - if position cannot be computed in given frame

getMinDate

public AbsoluteDate getMinDate()

Get the first date of the range.

Specified by:

getMinDate in interface BoundedPropagator

Returns:

the first date of the range

getMaxDate

public AbsoluteDate getMaxDate()

Get the last date of the range.

Specified by:

getMaxDate in interface BoundedPropagator

Returns:

the last date of the range

getFrame

public Frame getFrame()

Description copied from class: AbstractPropagator

Get the frame in which the orbit is propagated.

The propagation frame is the definition frame of the initial state, so this method should be called after this state has been set, otherwise it may return null.

Specified by:

getFrame in interface Propagator

Overrides:

getFrame in class AbstractPropagator

Returns:

frame in which the orbit is propagated

See Also:

Propagator.resetInitialState(SpacecraftState)

resetInitialState

public void resetInitialState(SpacecraftState state)
                       throws OrekitException

Reset the propagator initial state.

Specified by:

resetInitialState in interface Propagator

Overrides:

resetInitialState in class AbstractPropagator

Parameters:

state - new initial state to consider

Throws:

OrekitException - if initial state cannot be reset

resetIntermediateState

protected void resetIntermediateState(SpacecraftState state,
                                      boolean forward)
                               throws OrekitException

Reset an intermediate state.

Specified by:

resetIntermediateState in class AbstractAnalyticalPropagator

Parameters:

state - new intermediate state to consider

forward - if true, the intermediate state is valid for propagations after itself

Throws:

OrekitException - if initial state cannot be reset

getInitialState

public SpacecraftState getInitialState()
                                throws OrekitException

Get the propagator initial state.

Specified by:

getInitialState in interface Propagator

Overrides:

getInitialState in class AbstractPropagator

Returns:

initial state

Throws:

OrekitException - if state cannot be retrieved