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NOVAS3Equ2EclVec Method
Converts an equatorial position vector to an ecliptic position vector.

Namespace: ASCOM.Astrometry.NOVAS
Assembly: ASCOM.Astrometry (in ASCOM.Astrometry.dll) Version: 6.0.0.0 (6.3.0.2839)
Syntax
public short Equ2EclVec(
	double JdTt,
	CoordSys CoordSys,
	Accuracy Accuracy,
	double[] Pos1,
	ref double[] Pos2
)

Parameters

JdTt
Type: SystemDouble
TT Julian date of equator, equinox, and ecliptic used for
CoordSys
Type: ASCOM.AstrometryCoordSys
Coordinate system selection. 0 ... mean equator and equinox of date 'JdTt'; 1 ... true equator and equinox of date 'JdTt'; 2 ... ICRS
Accuracy
Type: ASCOM.AstrometryAccuracy
Selection for accuracy
Pos1
Type: SystemDouble
Position vector, referred to specified equator and equinox of date.
Pos2
Type: SystemDouble
Position vector, referred to specified ecliptic and equinox of date.

Return Value

Type: Int16
 0 ... everything OK
 1 ... invalid value of 'CoordSys'
 
Remarks
To convert an ICRS vector to an ecliptic vector (mean ecliptic and equinox of J2000.0 only), set 'CoordSys' = 2; the value of 'JdTt' can be set to anything, since J2000.0 is assumed. Except for the input to this case, all vectors are assumed to be with respect to a dynamical system.
See Also