agi.foundation.propagators

(agi.foundation.models-2024r2.jar)

Class CartesianOnePointPropagator

java.lang.Object

agi.foundation.infrastructure.DefinitionalObject

agi.foundation.propagators.CartesianOnePointPropagator

All Implemented Interfaces:

ICloneWithContext, IEnumerateDependencies, IEquatableDefinition, IFreezable

Direct Known Subclasses:

BallisticPropagator, GpsRinexPropagator, J2Propagator, J4Propagator, NavstarISGps200DPropagator, Sgp4Propagator, SimpleAscentPropagator, TwoBodyPropagator, WaypointPropagator

public abstract class CartesianOnePointPropagator
extends DefinitionalObject

The base class for simple one-point propagators that produce only Motion1.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	CartesianOnePointPropagator() Initializes a new instance.
protected	CartesianOnePointPropagator(CartesianOnePointPropagator existingInstance, CopyContext context) Initializes a new instance as a copy of an existing instance.

Method Summary

Modifier and Type	Method and Description
protected abstract boolean	checkForSameDefinition(CartesianOnePointPropagator other) Checks to determine if another instance has the same definition as this instance and returns true if it does.
protected boolean	checkForSameDefinition(DefinitionalObject other) Checks to determine if another instance has the same definition as this instance and returns true if it does.
protected int	computeCurrentDefinitionHashCode() Computes a hash code based on the current properties of this object.
PropagatorPoint	createPoint() Creates a Point that represents the motion produced by this propagator.
MotionEvaluator1<Cartesian>	getEvaluator() Gets an evaluator that can propagate at individual dates.
abstract MotionEvaluator1<Cartesian>	getEvaluator(EvaluatorGroup group) Gets an evaluator that can propagate at individual dates.
protected abstract ReferenceFrame	getMotionReferenceFrame() Gets the reference frame in which the motion is defined.
DateMotionCollection1<Cartesian>	propagate(JulianDate startDate, JulianDate stopDate, Duration timeStep, int order, ReferenceFrame outputReferenceFrame) Calculates position (and zero or more derivatives) for regular time steps over an interval.
DateMotionCollection1<Cartesian>	propagate(JulianDate startDate, JulianDate stopDate, Duration timeStep, int order, ReferenceFrame outputReferenceFrame, ITrackCalculationProgress tracker) Calculates position (and zero or more derivatives) for regular time steps over an interval.

Methods inherited from class agi.foundation.infrastructure.DefinitionalObject

areSameDefinition, areSameDefinition, areSameDefinition, areSameDefinition, areSameDefinition, clone, collectionItemsAreSameDefinition, collectionItemsAreSameDefinition, collectionItemsAreSameDefinition, dictionaryItemsAreSameDefinition, enumerateDependencies, freeze, freezeAggregatedObjects, getCollectionHashCode, getCollectionHashCode, getCollectionHashCode, getDefinitionHashCode, getDefinitionHashCode, getDefinitionHashCode, getDefinitionHashCode, getDefinitionHashCode, getDefinitionHashCode, getDictionaryHashCode, getIsFrozen, isSameDefinition, throwIfFrozen

Methods inherited from class java.lang.Object

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

Constructor Detail

CartesianOnePointPropagator

protected CartesianOnePointPropagator()

Initializes a new instance.

CartesianOnePointPropagator

protected CartesianOnePointPropagator(@Nonnull
                                      CartesianOnePointPropagator existingInstance,
                                      @Nonnull
                                      CopyContext context)

Initializes a new instance as a copy of an existing instance.

See ICloneWithContext.clone(CopyContext) for more information about how to implement this constructor in a derived class.

Parameters:

existingInstance - The existing instance to copy.

context - A CopyContext that controls the depth of the copy.

Throws:

ArgumentNullException - Thrown when existingInstance or context is null.

Method Detail

checkForSameDefinition

protected final boolean checkForSameDefinition(DefinitionalObject other)

Checks to determine if another instance has the same definition as this instance and returns true if it does. Derived classes MUST override this method and check all new fields introduced by the derived class for definitional equivalence. It is NOT necessary to check base class fields because the base class will already have done that. When overriding this method, you should NOT call the base implementation because it will return false for all derived-class instances. Derived classes should check the type of other to preserve the symmetric nature of IEquatableDefinition.isSameDefinition(java.lang.Object).

Specified by:

checkForSameDefinition in class DefinitionalObject

Parameters:

other - The other instance to compare to this one.

Returns:

true if the two objects are defined equivalently; otherwise false.

checkForSameDefinition

protected abstract boolean checkForSameDefinition(CartesianOnePointPropagator other)

Checks to determine if another instance has the same definition as this instance and returns true if it does. Derived classes MUST override this method and check all new fields introduced by the derived class for definitional equivalence. It is NOT necessary to check base class fields because the base class will already have done that. When overriding this method, you should NOT call the base implementation because it will return false for all derived-class instances. Derived classes should check the type of other to preserve the symmetric nature of IEquatableDefinition.isSameDefinition(java.lang.Object).

Parameters:

other - The other instance to compare to this one.

Returns:

true if the two objects are defined equivalently; otherwise false.

computeCurrentDefinitionHashCode

protected int computeCurrentDefinitionHashCode()

Computes a hash code based on the current properties of this object. Derived classes MUST override this method and compute a hash code that combines: a unique hash code seed, the base implementation result, and the hash codes of all new fields introduced by the derived class which are used in the CartesianOnePointPropagator.checkForSameDefinition(agi.foundation.infrastructure.DefinitionalObject) method.

Overrides:

computeCurrentDefinitionHashCode in class DefinitionalObject

Returns:

The computed hash code.

createPoint

@Nonnull
public PropagatorPoint createPoint()

Creates a Point that represents the motion produced by this propagator.

Returns:

The created point.

getEvaluator

@Nonnull
public final MotionEvaluator1<Cartesian> getEvaluator()

Gets an evaluator that can propagate at individual dates.

This evaluator propagates the orbit state. The result of evaluating will be a Motion1 corresponding to the orbital state at the given JulianDate expressed in the propagator's ReferenceFrame.

Note: when evaluating with this evaluator, it may be more efficient to specify times using an ArithmeticSafeStandard (get) to avoid the need to convert in order to perform the propagation. The length of a time step may be different in different TimeStandards. So be careful when specifying times.

Returns:

The evaluator.

getEvaluator

@Nonnull
public abstract MotionEvaluator1<Cartesian> getEvaluator(@Nonnull
                                                                   EvaluatorGroup group)

Gets an evaluator that can propagate at individual dates.

This evaluator propagates the orbit state. The result of evaluating will be a Motion1 corresponding to the orbital state at the given JulianDate expressed in the propagator's ReferenceFrame.

Note: when evaluating with this evaluator, it may be more efficient to specify times using an ArithmeticSafeStandard (get) to avoid the need to convert in order to perform the propagation. The length of a time step may be different in different TimeStandards. So be careful when specifying times.

Parameters:

group - The group with which to associate the new evaluator. By grouping evaluators that are often evaluated at the same Julian dates, common computations can be performed only once for the entire group instead of multiple times for each evaluator.

Returns:

The evaluator.

propagate

@Nonnull
public final DateMotionCollection1<Cartesian> propagate(@Nonnull
                                                                  JulianDate startDate,
                                                                  @Nonnull
                                                                  JulianDate stopDate,
                                                                  @Nonnull
                                                                  Duration timeStep,
                                                                  int order,
                                                                  @Nonnull
                                                                  ReferenceFrame outputReferenceFrame)

Calculates position (and zero or more derivatives) for regular time steps over an interval.

Note: when propagating, it may be more efficient to specify times using an ArithmeticSafeStandard (get) to avoid the need to convert in order to perform the propagation. The length of a time step may be different in different TimeStandards. So be careful when specifying times.

This method takes advantage of the ThreadingPolicy to improve performance.

Parameters:

startDate - The first date for which to calculate position and velocity.

stopDate - The last date for which to calculate position and velocity.

timeStep - The Duration between each ephemeris point.

order - The order of the highest derivative to compute. To compute just position, pass 0. To compute position and velocity (if available), pass 1. And so on.

outputReferenceFrame - The reference frame in which the generated ephemeris data is to be expressed.

Returns:

A list of date and motion for each step in the interval. The stopDate is always the last point in the list even when this makes the step between the second-to-last and last points less than the specified step.

propagate

public final DateMotionCollection1<Cartesian> propagate(@Nonnull
                                                        JulianDate startDate,
                                                        @Nonnull
                                                        JulianDate stopDate,
                                                        @Nonnull
                                                        Duration timeStep,
                                                        int order,
                                                        @Nonnull
                                                        ReferenceFrame outputReferenceFrame,
                                                        ITrackCalculationProgress tracker)

Calculates position (and zero or more derivatives) for regular time steps over an interval.

Note: when evaluating with this evaluator, it may be more efficient to specify times using an ArithmeticSafeStandard (get) to avoid the need to convert in order to perform the propagation. The length of a time step may be different in different TimeStandards. So be careful when specifying times.

This method takes advantage of the ThreadingPolicy to improve performance.

Parameters:

startDate - The first date for which to calculate position and velocity.

stopDate - The last date for which to calculate position and velocity.

timeStep - The Duration between each ephemeris point.

order - The order of the highest derivative to compute. To compute just position, pass 0. To compute position and velocity (if available), pass 1. And so on.

outputReferenceFrame - The reference frame in which the generated ephemeris data is to be expressed.

tracker - The object to which progress is reported and that is able to cancel this operation before it is complete.

Returns:

A list of date and motion for each step in the interval. The stopDate is always the last point in the list even when this makes the step between the second-to-last and last points less than the specified step.

getMotionReferenceFrame

@Nonnull
protected abstract ReferenceFrame getMotionReferenceFrame()

Gets the reference frame in which the motion is defined.

Returns:

The reference frame.