org.orekit.orbits

Enum OrbitType

java.lang.Object

java.lang.Enum<OrbitType>

org.orekit.orbits.OrbitType

All Implemented Interfaces:

Serializable, Comparable<OrbitType>

public enum OrbitType
extends Enum<OrbitType>

Enumerate for orbital parameters types.

Enum Constant Summary

Enum Constants

Enum Constant and Description
CARTESIAN Type for propagation in Cartesian parameters.
CIRCULAR Type for propagation in circular parameters.
EQUINOCTIAL Type for propagation in equinoctial parameters.
KEPLERIAN Type for propagation in Keplerian parameters.

Method Summary

Modifier and Type	Method and Description
abstract <T extends RealFieldElement<T>> FieldOrbit<T>	convertType(FieldOrbit<T> orbit) Convert an orbit to the instance type.
abstract Orbit	convertType(Orbit orbit) Convert an orbit to the instance type.
abstract ParameterDriversList	getDrivers(double dP, Orbit orbit, PositionAngle type) Get parameters drivers initialized from a reference orbit.
abstract Orbit	mapArrayToOrbit(double[] array, double[] arrayDot, PositionAngle type, AbsoluteDate date, double mu, Frame frame) Convert state array to orbital parameters.
abstract <T extends RealFieldElement<T>> FieldOrbit<T>	mapArrayToOrbit(T[] array, T[] arrayDot, PositionAngle type, FieldAbsoluteDate<T> date, T mu, Frame frame) Convert state array to orbital parameters.
abstract <T extends RealFieldElement<T>> void	mapOrbitToArray(FieldOrbit<T> orbit, PositionAngle type, T[] stateVector, T[] stateVectorDot) Convert orbit to state array.
abstract void	mapOrbitToArray(Orbit orbit, PositionAngle type, double[] stateVector, double[] stateVectorDot) Convert orbit to state array.
protected double[]	scale(double dP, Orbit orbit) Compute scaling factor for parameters drivers.
static OrbitType	valueOf(String name) Returns the enum constant of this type with the specified name.
static OrbitType[]	values() Returns an array containing the constants of this enum type, in the order they are declared.

Methods inherited from class java.lang.Enum

clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Enum Constant Detail

CARTESIAN

public static final OrbitType CARTESIAN

Type for propagation in Cartesian parameters.

CIRCULAR

public static final OrbitType CIRCULAR

Type for propagation in circular parameters.

EQUINOCTIAL

public static final OrbitType EQUINOCTIAL

Type for propagation in equinoctial parameters.

KEPLERIAN

public static final OrbitType KEPLERIAN

Type for propagation in Keplerian parameters.

Method Detail

values

public static OrbitType[] values()

Returns an array containing the constants of this enum type, in the order they are declared. This method may be used to iterate over the constants as follows:

for (OrbitType c : OrbitType.values())
    System.out.println(c);

Returns:

an array containing the constants of this enum type, in the order they are declared

valueOf

public static OrbitType valueOf(String name)

Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)

Parameters:

name - the name of the enum constant to be returned.

Returns:

the enum constant with the specified name

Throws:

IllegalArgumentException - if this enum type has no constant with the specified name

NullPointerException - if the argument is null

convertType

public abstract Orbit convertType(Orbit orbit)

Convert an orbit to the instance type.

The returned orbit is the specified instance itself if its type already matches, otherwise, a new orbit of the proper type created

Parameters:

orbit - orbit to convert

Returns:

converted orbit with type guaranteed to match (so it can be cast safely)

mapOrbitToArray

public abstract void mapOrbitToArray(Orbit orbit,
                                     PositionAngle type,
                                     double[] stateVector,
                                     double[] stateVectorDot)

Convert orbit to state array.

Note that all implementations of this method must be consistent with the implementation of the Orbit.getJacobianWrtCartesian method for the corresponding orbit type in terms of parameters order and meaning.

Parameters:

orbit - orbit to map

type - type of the angle

stateVector - flat array into which the state vector should be mapped (it can have more than 6 elements, extra elements are untouched)

stateVectorDot - flat array into which the state vector derivative should be mapped (it can be null if derivatives are not desired, and it can have more than 6 elements, extra elements are untouched)

mapArrayToOrbit

public abstract Orbit mapArrayToOrbit(double[] array,
                                      double[] arrayDot,
                                      PositionAngle type,
                                      AbsoluteDate date,
                                      double mu,
                                      Frame frame)

Convert state array to orbital parameters.

Note that all implementations of this method must be consistent with the implementation of the Orbit.getJacobianWrtCartesian method for the corresponding orbit type in terms of parameters order and meaning.

Parameters:

array - state as a flat array (it can have more than 6 elements, extra elements are ignored)

arrayDot - state derivative as a flat array (it can be null, in which case Keplerian motion is assumed, and it can have more than 6 elements, extra elements are ignored)

type - type of the angle

date - integration date

mu - central attraction coefficient used for propagation (m³/s²)

frame - frame in which integration is performed

Returns:

orbit corresponding to the flat array as a space dynamics object

convertType

public abstract <T extends RealFieldElement<T>> FieldOrbit<T> convertType(FieldOrbit<T> orbit)

Convert an orbit to the instance type.

The returned orbit is the specified instance itself if its type already matches, otherwise, a new orbit of the proper type created

Type Parameters:

T - RealFieldElement used

Parameters:

orbit - orbit to convert

Returns:

converted orbit with type guaranteed to match (so it can be cast safely)

mapOrbitToArray

public abstract <T extends RealFieldElement<T>> void mapOrbitToArray(FieldOrbit<T> orbit,
                                                                     PositionAngle type,
                                                                     T[] stateVector,
                                                                     T[] stateVectorDot)

Convert orbit to state array.

Note that all implementations of this method must be consistent with the implementation of the Orbit.getJacobianWrtCartesian method for the corresponding orbit type in terms of parameters order and meaning.

Type Parameters:

T - RealFieldElement used

Parameters:

orbit - orbit to map

type - type of the angle

stateVector - flat array into which the state vector should be mapped (it can have more than 6 elements, extra elements are untouched)

stateVectorDot - flat array into which the state vector derivative should be mapped (it can be null if derivatives are not desired, and it can have more than 6 elements, extra elements are untouched)

mapArrayToOrbit

public abstract <T extends RealFieldElement<T>> FieldOrbit<T> mapArrayToOrbit(T[] array,
                                                                              T[] arrayDot,
                                                                              PositionAngle type,
                                                                              FieldAbsoluteDate<T> date,
                                                                              T mu,
                                                                              Frame frame)

Convert state array to orbital parameters.

Note that all implementations of this method must be consistent with the implementation of the Orbit.getJacobianWrtCartesian method for the corresponding orbit type in terms of parameters order and meaning.

Type Parameters:

T - RealFieldElement used

Parameters:

array - state as a flat array (it can have more than 6 elements, extra elements are ignored)

arrayDot - state derivative as a flat array (it can be null, in which case Keplerian motion is assumed,

type - type of the angle

date - integration date

mu - central attraction coefficient used for propagation (m³/s²)

frame - frame in which integration is performed

Returns:

orbit corresponding to the flat array as a space dynamics object

getDrivers

public abstract ParameterDriversList getDrivers(double dP,
                                                Orbit orbit,
                                                PositionAngle type)

Get parameters drivers initialized from a reference orbit.

Parameters:

dP - user specified position error

orbit - reference orbit

type - type of the angle

Returns:

parameters drivers initialized from reference orbit

scale

protected double[] scale(double dP,
                         Orbit orbit)

Compute scaling factor for parameters drivers.

The scales are estimated from partial derivatives properties of orbits, starting from a scalar position error specified by the user. Considering the energy conservation equation V = sqrt(mu (2/r - 1/a)), we get at constant energy (i.e. on a Keplerian trajectory):

 V² r |dV| = mu |dr|
 

So we deduce a scalar velocity error consistent with the position error. From here, we apply orbits Jacobians matrices to get consistent scales on orbital parameters.

Parameters:

dP - user specified position error

orbit - reference orbit

Returns:

scaling factor array