acoustotreams.ScalarSphericalWaveBasis.default

classmethod ScalarSphericalWaveBasis.default(lmax, nmax=1, positions=None)

Default basis for a given maximum multipolar degree.

By default, modes are grouped into separate blocks for each position index in ascending order. Within each block, modes are sorted by degree \(l\) (lowest first) and then by order :math:m from \(m = -l\) to \(m = l\).

Example

>>> acoustotreams.ScalarSphericalWaveBasis.default(2)
ScalarSphericalWaveBasis(
    pidx=[0 0 0 0 0 0 0 0 0],
    l=[0 1 1 1 2 2 2 2 2],
    m=[ 0 -1  0  1 -2 -1  0  1  2],
    positions=[[0. 0. 0.]],
)
>>> acoustotreams.ScalarSphericalWaveBasis.default(0, 2, [[0, 0, 1.], [0, 0, -1.]])
ScalarSphericalWaveBasis(
    pidx=[0 1],
    l=[0 0],
    m=[0 0],
    positions=[[ 0.  0.  1.], [ 0.  0. -1.]],
)

Parameters:

• lmax (int) – Maximum multipolar degree.

• nmax (int, optional) – Number of positions. Defaults to 1.

• positions (array_like of float, optional) – Positions of the expansion centers (m). Defaults to [[0, 0, 0]].