def test_distributed_qft_agreement(nqubits):
"""Check ``_DistributedQFT`` agrees with normal ``QFT``."""
initial_state = utils.random_numpy_state(nqubits)
exact_state = exact_qft(initial_state)
c = models._DistributedQFT(nqubits)
final_state = c(np.copy(initial_state)).numpy()
np.testing.assert_allclose(final_state, exact_state, atol=_atol)
def test_distributed_qft_error():
"""Check that ``_DistributedQFT`` raises error if not sufficient qubits."""
with pytest.raises(NotImplementedError):
c = models._DistributedQFT(2, accelerators={"/GPU:0": 4})
with pytest.raises(NotImplementedError):
c = models.QFT(10, with_swaps=False, accelerators={"/GPU:0": 2})