xcc_v_convert

This routine rotates a 3D coordinate vector from one astronomical coordinate system to another.

Location in HEALPix directory tree: src/f90/mod/coord_v_convert.f90 

FORMAT

call xcc_v_convert( ivector, iepoch, oepoch, isys, osys, ovector )

ARGUMENTS

name & dimensionality	kind	in/out	description
ivector(1:3)	DP	IN	3D coordinate vector of one astronomical object, in the input coordinate system.
iepoch	DP	IN	epoch of the input astronomical coordinate system.
oepoch	DP	IN	epoch of the output astronomical coordinate system.
isys(len=*)	CHR	IN	input coordinate system, should be one of 'E'=Ecliptic, 'G'=Galactic, 'C'/'Q'=Celestial/eQuatorial.
osys(len=*)	CHR	IN	output coordinate system, same choice as above.
ovector(1:3)	DP	IN	3D coordinate vector of the same object, in the output coordinate system.

EXAMPLE:

use healpix_types
use coord_v_convert, only: xcc_v_convert
real(dp) :: vecin(1:3), vecout(1:3)
vecin = (/ 0_dp, 0_dp, 1_dp /)
call xcc_v_convert(vecin, 2000.0_dp, 2000.0_dp, 'g', 'c', vecout)

Will produce in vecout the location in Celestial coordinates (2000 epoch) of the North Galactic Pole (defined in vecin)

RELATED ROUTINES

This section lists the routines related to xcc_v_convert

coordsys2euler_zyz

produces the Euler angles $\psi, \theta, \varphi$ in (Z,Y,Z) convention for rotation between standard astronomical coordinate systems.

ang2vec, vec2ang

Routine to convert spherical coordinates (co-latitude and longitude) into 3D vector coordinates and vice-versa.