SCULIB_APPARENT_2_TP - calculate tangent plane coordinates from apparent RA, Decs

Description:

This routine converts a list of apparent RA,Decs to tangent plane offsets from a tangent point whose position is also given in apparent RA,Dec. In addition, a rotation is applied to the tangent plane so that it can be aligned with a coordinate system other than apparent RA,Dec, and a shift is added to allow the map to be moved about in that output frame.

Invocation:

CALL SCULIB_APPARENT_2_TP (N_POS, BOL_XPOS, BOL_YPOS, RA_CEN, DEC_CEN, ROTATION, SHIFT_DX, SHIFT_DY, STATUS)

Arguments:

N_POS = INTEGER (Given)

the number of positions to be converted

BOL_XPOS (N_POS) = DOUBLE PRECISION (Given and returned)

apparent RA on input (radians), x tangent plane offset on output (radians)

BOL_YPOS (N_POS) = DOUBLE PRECISION (Given and returned)

apparent Dec on input (radians), y tangent plane offset on output (radians)

RA_CEN = DOUBLE PRECISION (Given)

apparent RA of tangent point (radians)

DEC_CEN = DOUBLE PRECISION (Given)

apparent Dec of tangent point (radians)

ROTATION = DOUBLE PRECISION (Given)

angle between output North and apparent North (radians, measured anticlockwise from output North)

SHIFT_DX = DOUBLE PRECISION (Given)

value to be added to x offsets (radians)

SHIFT_DY = DOUBLE PRECISION (Given)

value to be added to y offsets (radians)

STATUS = INTEGER (Given and returned)

Copyright

Copyright ©1995,1996,1997,1998,1999 Particle Physics and Astronomy Research Council. All Rights Reserved.