treams.SphericalWaveBasis.ebcm

classmethod SphericalWaveBasis.ebcm(lmax, nmax=1, mmax=-1, positions=None)

Order of modes suited for ECBM.

In comparison to default() this order prioritises blocks of the z-projection of the angular momentum \(m\) over the angular momentum \(l\). This is useful to get block-diagonal matrices for the extended boundary condition method (EBCM).

Example

>>> SphericalWaveBasis.ebcm(2)
SphericalWaveBasis(
    pidx=[0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0],
    l=[2 2 1 1 2 2 1 1 2 2 1 1 2 2 2 2],
    m=[-2 -2 -1 -1 -1 -1  0  0  0  0  1  1  1  1  2  2],
    pol=[1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0],
    positions=[[0. 0. 0.]],
)

Parameters:

• lmax (int) – Maximal multipolar order.

• nmax (int, optional) – Number of particles, defaults to 1.

• mmax (int, optional) – Maximal value of |m|. If ommitted or set to -1 it is taken equal to lmax.

• positions (array-like, optional) – Positions of the origins.

Returns:

tuple