galpy.util.coords.pupv_to_vRvz¶

galpy.util.coords.pupv_to_vRvz(pu, pv, u, v, delta=1.0, oblate=False)[source]¶

Calculate cylindrical vR and vz from momenta in prolate or oblate confocal u and v coordinates for a given focal length delta.

Parameters:

pu (float or numpy.ndarray) – Momentum in u.
pv (float or numpy.ndarray) – Momentum in v.
u (float or numpy.ndarray) – Confocal u.
v (float or numpy.ndarray) – Confocal v.
delta (float or numpy.ndarray, optional) – Focus. Default is 1.0.
oblate (bool, optional) – If True, compute oblate confocal coordinates instead of prolate. Default is False.

Returns:

(vR, vz)

Return type:

tuple

Notes

2017-12-04 - Written - Bovy (UofT)