conatus.expert.SphereBasis

class conatus.expert.SphereBasis(coord, size, radius=1.0, dealias=REQUIRED)

Bases: Basis

Colatitude part of the spin-weighted spherical harmonics (Vasil et al. 2019), attached to theta of S2Coordinates or SphericalCoordinates, next to a Fourier basis in phi.

size = Lmax + 1 degrees l = 0..Lmax; a spin-s component of azimuthal mode m holds the degrees l >= max(|m|, |s|) (triangular truncation). radius is the sphere’s radius on S2Coordinates (ignored in SphericalCoordinates, where the radius is the coordinate r). Grid: Gauss-Legendre nodes in cos(theta), floor(size * dealias) of them. Note: Dedalus’s real SphereBasis of shape (Nphi, Ntheta) has Lmax = Ntheta - 2, i.e. size = Ntheta - 1 here (declared, never inferred).

Parameters:

• coord (Coordinate)

• size (int)

• radius (float)

• dealias (Any)

family = 'spin-weighted spherical harmonics (colatitude part, Jacobi in cos theta)'

property Lmax: int

coeff_space()

Return type:

str