galpy.potential.Potential.z2deriv

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

Evaluate the second vertical derivative.

Parameters:

  • R (float or Quantity) – Galactocentric radius.

  • z (float or Quantity) – Vertical height.

  • phi (float or Quantity, optional) – Galactocentric azimuth (default: 0.0).

  • t (float or Quantity, optional) – Time (default: 0.0).

Returns:

d2phi/dz2.

Return type:

float or Quantity

Notes

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