compute_coeffs_discrete#

gala.potential.scf.compute_coeffs_discrete(xyz, mass, nmax, lmax, r_s, skip_odd=False, skip_even=False, skip_m=False, compute_var=False, pool=None)[source]#

Compute the expansion coefficients for representing the density distribution of input points as a basis function expansion. The points, xyz, are assumed to be samples from the density distribution.

Warning

GSL is required for this function, see the Installation instructions for more details

Parameters:

xyzarray_like: Samples from the density distribution. Should have shape (n_samples, 3).
massarray_like: Mass of each sample. Should have shape (n_samples,).
nmaxint: Maximum value of n for the radial expansion.
lmaxint: Maximum value of l for the spherical harmonics.
r_snumeric: Scale radius.
skip_oddbool (optional): Skip the odd terms in the angular portion of the expansion. For example, only take \(l=0, 2, 4, ...\)
skip_evenbool (optional): Skip the even terms in the angular portion of the expansion. For example, only take \(l=1, 3, 5, ...\)
skip_mbool (optional): Ignore terms with \(m > 0\).
compute_varbool (optional): Also compute the variances (and covariances) of the coefficients.
poolPool, schwimmbad.BasePool (optional): A multi-processing or other parallel processing pool to use to distribute the tasks of computing the coefficients for each n,l,m term. The pool instance must have a map() method.

Returns:

Snlmndarray: The value of the cosine expansion coefficient.
Tnlmndarray: The value of the sine expansion coefficient.
STcovarndarray, optional: If compute_var==True, this also computes and returns the covariance matrix of the coefficients.