galpy.df.diskdf.sigma2surfacemass¶
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diskdf.
sigma2surfacemass
(R, romberg=False, nsigma=None, relative=False)[source]¶ NAME:
sigma2surfacemassPURPOSE:
calculate the product sigma_R^2 x surface-mass at R by marginalizing over velocityINPUT:
R - radius at which to calculate the sigma_R^2 x surfacemass density (can be Quantity)OPTIONAL INPUT:
nsigma - number of sigma to integrate the velocities overKEYWORDS:
romberg - if True, use a romberg integrator (default: False)OUTPUT:
sigma_R^2 x surface-mass at RHISTORY:
2010-03-XX - Written - Bovy (NYU)