galpy.df.diskdf.sigma2

diskdf.sigma2(R, romberg=False, nsigma=None, phi=0.0)[source]

NAME:

sigma2

PURPOSE:

calculate sigma_R^2 at R by marginalizing over velocity

INPUT:

R - radius at which to calculate sigma_R^2 density (can be Quantity)

OPTIONAL INPUT:

nsigma - number of sigma to integrate the velocities over

KEYWORDS:

romberg - if True, use a romberg integrator (default: False)

OUTPUT:

sigma_R^2 at R

HISTORY:

2010-03-XX - Written - Bovy (NYU)