If periodic is True and the trajectory contains unitcell
information, we will treat dihedrals that cross periodic images
using the minimum image convention.
opt : bool, default=True
Use an optimized native library to calculate angles.
Returns:
indices : np.ndarray, shape=(n_omega, 4)
The indices of the atoms involved in each of the omega dihedral angles
angles : np.ndarray, shape=(n_frames, n_omega)
The value of the dihedral angle for each of the angles in each of
the frames.