galpy.util.coords.spher_to_cyl_vec¶

galpy.util.coords.spher_to_cyl_vec(vr, vT, vtheta, theta)[source]¶

Transform vectors from spherical polar to cylindrical coordinates.

Parameters:

vr (float or numpy.ndarray) – Galactocentric spherical radial velocity
vT (float or numpy.ndarray) – Galactocentric spherical azimuthal velocity
vtheta (float or numpy.ndarray) – Galactocentric spherical polar velocity
theta (float or numpy.ndarray) – Galactocentric spherical polar angle

Returns:

A tuple containing the Galactocentric cylindrical radial velocity, azimuthal velocity, and vertical velocity in that order.

Return type:

tuple

Notes