NAME:
pmllpmbb_to_pmrapmdec
PURPOSE:
rotate proper motions in (l,b) into proper motions in (ra,dec)
INPUT:
pmll - proper motion in l (multplied with cos(b)) [mas/yr]
pmbb - proper motion in b [mas/yr]
l - Galactic longitude
b - Galactic lattitude
degree - if True, l and b are given in degrees (default=False)
epoch - epoch of ra,dec (right now only 2000.0 and 1950.0 are supported)
OUTPUT:
(pmra,pmdec), for vector inputs [:,2]
HISTORY:
2010-04-07 - Written - Bovy (NYU)