galpy.potential.scf_compute_coeffs_nbody¶
This function is the equivalent to galpy.potential.scf_compute_coeffs but computing the coefficients based on an N-body representation of the density.
Note: This function computes Acos and Asin as defined in Hernquist & Ostriker (1992), except that we multiply Acos and Asin by 2 such that the density from Galpy’s Hernquist Potential corresponds to \(Acos = \delta_{0n}\delta_{0l}\delta_{0m}\) and \(Asin = 0\).
- galpy.potential.scf_compute_coeffs_nbody(pos, N, L, mass=1.0, a=1.0)[source]¶
NAME:
scf_compute_coeffs_nbody
PURPOSE:
Numerically compute the expansion coefficients for a given $N$-body set of points
INPUT:
pos - positions of particles in rectangular coordinates with shape [3,n]
N - size of the Nth dimension of the expansion coefficients
L - size of the Lth and Mth dimension of the expansion coefficients
mass= (1.) mass of particles (scalar or array with size n)
a= (1.) parameter used to scale the radius
OUTPUT:
(Acos,Asin) - Expansion coefficients for density dens that can be given to SCFPotential.__init__
HISTORY:
2020-11-18 - Written - Morgan Bennett (UofT)