mdtraj.compute_psi

mdtraj.compute_psi(traj, periodic=True, opt=True)

Calculate the psi torsions of a trajectory.

Parameters:

traj : Trajectory

Trajectory for which you want dihedrals.

periodic : bool, default=True

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_psi, 4)

The indices of the atoms involved in each of the psi dihedral angles

angles : np.ndarray, shape=(n_frames, n_psi)

The value of the dihedral angle for each of the angles in each of the frames.