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.

Version 3.31, 2017-01-06