galpy.potential.Potential.phi2deriv¶
-
Potential.
phi2deriv
(R, z, phi=0.0, t=0.0)[source]¶ NAME:
phi2derivPURPOSE:
evaluate the second azimuthal derivativeINPUT:
R - Galactocentric radius (can be Quantity)
Z - vertical height (can be Quantity)
phi - Galactocentric azimuth (can be Quantity)
t - time (can be Quantity)
OUTPUT:
d2Phi/dphi2HISTORY:
2013-09-24 - Written - Bovy (IAS)