galpy.potential.scf_compute_coeffs_axi_nbody¶
This function is the equivalent to galpy.potential.scf_compute_coeffs_axi 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 by 2 such that the density from Galpy’s Hernquist Potential corresponds to \(Acos = \delta_{0n}\delta_{0l}\delta_{0m}\).
Further note that this function is a specification of galpy.potential.scf_compute_coeffs_nbody where \(Acos_{nlm} = 0\) at \(m\neq0\) and \(Asin_{nlm} = None\).
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galpy.potential.
scf_compute_coeffs_axi_nbody
(pos, N, L, mass=1.0, a=1.0)[source]¶ NAME:
scf_compute_coeffs_axi_nbodyPURPOSE:
Numerically compute the expansion coefficients for a given $N$-body set of points assuming that the density is axisymmetricINPUT:
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 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:
2021-02-22 - Written based on general code - Bovy (UofT)