def test_cog(self):
"""
Test if reduced r & weights calculates centre of geometry accurately.
"""
r = Gyration._get_reduced_r(cluster, None)
weights = Gyration._get_weights(cluster, None)
assert np.abs(np.sum(r * weights)) < 1e-7
def test_com(self):
"""
Test if reduced r & weights calculates centre of mass accurately.
"""
weights = cluster.atoms.masses
r = Gyration._get_reduced_r(cluster, weights)
weights = Gyration._get_weights(cluster, weights)
assert np.abs(np.sum(r * weights)) < 1e-7