mpsmpo_test.py 文件源码

def test_mps_to_mpo(nr_sites, local_dim, rank, rgen):
    mps = factory.random_mps(nr_sites, local_dim, rank, randstate=rgen)
    # Instead of calling the two functions, we call mps_to_mpo(),
    # which does exactly that:
    #   mps_as_puri = mp.mps_as_local_purification_mps(mps)
    #   mpo = mp.pmps_to_mpo(mps_as_puri)
    mpo = mm.mps_to_mpo(mps)
    # This is also a test of mp.mps_as_local_purification_mps() in the
    # following sense: Local purifications are representations of
    # mixed states. Therefore, compare mps and mps_as_puri by
    # converting them to mixed states.
    state = mps.to_array()
    state = np.outer(state, state.conj())
    state.shape = (local_dim,) * (2 * nr_sites)
    state2 = mpo.to_array_global()
    assert_array_almost_equal(state, state2)