ElementConvert(Variable, Variable, TimeSpan, Array, Variable) Function

 Top 

Description

Converts the orbital state specified by elementArray from the fromSystem element set to the toSystem element set, using the central body gravitational parameter specified by mu. This overload can only be used when the fromSystem or toSystem is Spherical Lat-Long. The order of the elements for each element set are listed below (using the Spacecraft properties):

 

- CARTESIAN: X, Y, Z, VX, VY, VZ

- KEPLERIAN: A, E, I, RAAN, W, TA

- NONSINGULAR_KEPLERIAN: NonSingularA, NonSingularE1, NonSingularE2, NonSingularE3, NonSingularE4, NonSingularE5

- EQUINOCTIAL: EquinoctialA, EquinoctialH, EquinoctialK, EquinoctialP, EquinoctialQ, EquinoctialLongitude

- BROUWER_MEAN: BL_A, BL_E, BL_I, BL_RAAN, BL_W, BL_MA

- J2_BROUWER_MEAN: BLJ2A, BLJ2E, BLJ2I, BLJ2RAAN, BLJ2W, BLJ2MA

- SPHERICAL: SphericalRadius, RA, DEC, Vi, SphericalAzimuth, VerticalFPA

- SPHERICAL_LATLONG: LatLongRadius, Latitude, Longitude, LatLongVi, LatLongAzimuth, HorizontalFPA

- SGP4: Mean I, Mean RAAN, Mean E, Mean W, Mean MA, Mean MeanMotion

- MODIFIED_EQUINOCTIAL: ModifiedEquinoctialP, ModifiedEquinoctialF, ModifiedEquinoctialG, ModifiedEquinoctialH, ModifiedEquinoctialK, ModifiedEquinoctialL

- SGP4 EQUINOCTIAL: Mean EquinoctialH, Mean EquinoctialK, Mean EquinoctialP, Mean EquinoctialQ, Mean EquinoctialLongitude, Mean EquinoctialMeanMotion

 

Note, when used to convert an element set into SGP4 elements this function is not compatible with the SGP4/SDP4 propagator.

 

Timing Precision Mode

This page describes functionality in nanosecond timing precision mode.

 

Function Signature

ElementConvert(

Variable fromSystem,

Variable toSystem,

TimeSpan epoch,

Array elementArray,

Variable mu)

 

 

Arguments

fromSystem

Description:

Element set of input state.

Valid Values:

Value

Label

1

CARTESIAN

2

KEPLERIAN

3

NONSINGULAR_KEPLERIAN

4

EQUINOCTIAL

5

BROUWER_MEAN

6

J2_BROUWER_MEAN

7

SPHERICAL

8

SPHERICAL_LATLONG

9

SGP4

10

MODIFIED_EQUINOCTIAL

11

SGP4 EQUINOCTIAL

 

 

 

toSystem

Description:

Element set of output state.

Valid Values:

Value

Label

1

CARTESIAN

2

KEPLERIAN

3

NONSINGULAR_KEPLERIAN

4

EQUINOCTIAL

5

BROUWER_MEAN

6

J2_BROUWER_MEAN

7

SPHERICAL

8

SPHERICAL_LATLONG

9

SGP4

10

MODIFIED_EQUINOCTIAL

11

SGP4 EQUINOCTIAL

 

 

 

epoch

Description:

The TAI epoch of the orbital state in modified Julian date format.

 

 

elementArray

Description:

A six-element array containing the orbital state in the input element set.

 

When converting TO Spherical Lat-Long. or SGP4, the input state is assumed to be referenced to the ICRF. When converting FROM Spherical Lat-Long., the input state is assumed to be in the Earth Fixed coordinate system. When converting FROM SGP4, the input state is assumed to be in the TEME coordinate system.

 

For all other conversions, the output state will be referenced to the same coordinate system as the input state.

Required Size:

At least 6

 

 

mu

Description:

Specifies the value of Mu (gravitational parameter of central body) to use in the element conversion.

Units:

km3/s2

Valid Range:

mu > 0

 

 

 

Return Value

Type:

Array of number (size = 6)

 

 

Returns a six-element array containing the orbital state in the output element set. When converting TO Spherical Lat-Long., the output state will be referenced to the Earth Fixed coordinate system. When converting FROM Spherical Lat-Long., the output state will be referenced to the ICRF.

 

Syntax

myArray1 = ElementConvert(myVariable1, myVariable2, myTimeSpan1, myArray2, myVariable3);

 

 

See also

ElementConvert

Orbit Element Types