Function vector_wave 

pub fn vector_wave(
    family: Family,
    label: WaveLabel,
    args: [Complex; 6],
    helicity: bool,
) -> Result<[Complex; 3]>

Evaluate a vector wave in its local component frame.

Harmonics use (theta,phi), spherical waves (kr,theta,phi), cylinders (kz,k_rho*rho,phi,z,k), and planes (kx,ky,kz,x,y,z). Unused arguments are zero.

Upstream: treams.special.vsh_X, vsh_Y, vsh_Z, vsw_*, vcw_* and vpw_*.