Function _compute_sph_harm

mne/transforms.py:938–950

Compute complex spherical harmonics of spherical coordinates.

(order, az, pol)

def _compute_sph_harm(order, az, pol):
    """Compute complex spherical harmonics of spherical coordinates."""
    out = np.empty((len(az), _get_n_moments(order) + 1))
    # _deg_ord_idx(0, 0) = -1 so we're actually okay to use it here
    for degree in range(order + 1):
        for order_ in range(degree + 1):
            sph = sph_harm_y(degree, order_, pol, az)
            out[:, _deg_ord_idx(degree, order_)] = _sh_complex_to_real(sph, order_)
            if order_ > 0:
                out[:, _deg_ord_idx(degree, -order_)] = _sh_complex_to_real(
                    _sh_negate(sph, order_), -order_
                )
    return out


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