galpy.potential.Potential.z2deriv

Potential.z2deriv(R, z, phi=0.0, t=0.0)[source]

NAME:

z2deriv

PURPOSE:

evaluate the second vertical derivative

INPUT:

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/dz2

HISTORY:

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