astGetRefPosastGetRefPos - Return the reference position in a specified celestial coordinate system

Description:
This function returns the reference position (specified by attributes RefRARefRA and RefDecRefDec) converted to the celestial coordinate system represented by a supplied SkyFrameSkyFrame. The celestial longitude and latitude values are returned in radians.
Synopsis:
void astGetRefPos( AstSpecFrame $*$this, AstSkyFrame $*$frm, double $*$lon, double $*$lat )
Parameters:
this
Pointer to the SpecFrameSpecFrame.
frm
Pointer to the SkyFrame which defines the required celestial coordinate system. If NULL is supplied, then the longitude and latitude values are returned as FK5 J2000 RA and Dec values.
lon
A pointer to a double in which to store the longitude of the reference point, in the coordinate system represented by the supplied SkyFrame (radians).
lat
A pointer to a double in which to store the latitude of the reference point, in the coordinate system represented by the supplied SkyFrame (radians).
Notes:
  • Values of AST__BAD will be returned if this function is invoked with the AST error status set, or if it should fail for any reason.