# galpy.potential.evaluatez2derivs¶

galpy.potential.evaluatez2derivs(Pot, R, z, phi=None, t=0.0)[source]

NAME:

evaluatez2derivs

PURPOSE:

convenience function to evaluate a possible sum of potentials

INPUT:

Pot - a potential or list of potentials (dissipative forces in such a list are ignored)

R - cylindrical Galactocentric distance (can be Quantity)

z - distance above the plane (can be Quantity)

phi - azimuth (optional; can be Quantity)

t - time (optional; can be Quantity)

OUTPUT:

d2Phi/d2z(R,z,phi,t)

HISTORY:

2012-07-25 - Written - Bovy (IAS)