galpy.potential.Potential.vterm
galpy.potential.Potential.zforce
Potential.
z2deriv
NAME:
PURPOSE:
evaluate the second vertical derivative
INPUT:
R - Galactocentric radius Z - vertical height phi - Galactocentric azimuth t - time
R - Galactocentric radius
Z - vertical height
phi - Galactocentric azimuth
t - time
OUTPUT:
d2phi/dz2
HISTORY:
2012-07-25 - Written - Bovy (IAS@MPIA)