galpy.util.coords.pmrapmdec_to_custom

galpy.util.coords.pmrapmdec_to_custom(pmra, pmdec, ra, dec, T=None, degree=False)[source]

NAME:

pmrapmdec_to_custom

PURPOSE:

rotate proper motions in (ra,dec) to proper motions in a custom set of sky coordinates (phi1,phi2)

INPUT:

pmra - proper motion in ra (multplied with cos(dec)) [mas/yr]

pmdec - proper motion in dec [mas/yr]

ra - right ascension

dec - declination

T= matrix defining the transformation: new_rect= T dot old_rect, where old_rect = [cos(dec)cos(ra),cos(dec)sin(ra),sin(dec)] and similar for new_rect

degree= (False) if True, ra and dec are given in degrees (default=False)

OUTPUT:

(pmphi1 x cos(phi2),pmph2) for vector inputs [:,2]

HISTORY:

2016-10-24 - Written - Bovy (UofT/CCA)

2019-03-09 - uses custom_to_radec - Nathaniel Starkman (UofT)