galpy.util.coords.pmrapmdec_to_custom

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

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

Parameters:

  • pmra (float or numpy.ndarray) – Proper motion in ra (multiplied with cos(dec)) [mas/yr].

  • pmdec (float or numpy.ndarray) – Proper motion in dec [mas/yr].

  • ra (float or numpy.ndarray) – Right ascension.

  • dec (float or numpy.ndarray) – Declination.

  • T (numpy.ndarray, optional) – 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 (bool, optional) – If True, ra and dec are given in degrees (default=False).

Returns:

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

Return type:

tuple

Notes

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

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