def test_invalid_n_samples(self, d):
"""Test if function raises a ``ValueError`` when a number of samples less than one is
requested."""
with pytest.raises(ValueError,
match="Number of samples must be at least one"):
in_state, t, U, w, ns, cf = d
dynamics.sample_fock(in_state, t, U, w, 0, cf)
def test_negative_input_state(self, d):
"""Test if function raises a ``ValueError`` when input state contains negative values."""
with pytest.raises(
ValueError,
match="Input state must not contain negative values"):
in_state, t, U, w, ns, cf = d
dynamics.sample_fock([-i for i in in_state], t, U, w, ns, cf)
def test_zero_frequency(self, d):
"""Test if function raises a ``ValueError`` when zero frequencies are given."""
with pytest.raises(
ValueError,
match="Vibrational frequencies must be larger than zero"):
in_state, t, U, w, ns, cf = d
dynamics.sample_fock(in_state, t, U, 0.0 * w, ns, cf)
def test_invalid_loss(self, d):
"""Test if function raises a ``ValueError`` when the loss parameter is specified outside
of range."""
with pytest.raises(
ValueError,
match="Loss parameter must take a value between zero and one"):
in_state, t, U, w, ns, cf = d
dynamics.sample_fock(in_state, t, U, w, ns, cf, -1)
def test_complex_unitary(self, d):
"""Test if function raises a ``ValueError`` when a complex unitary is given."""
with pytest.raises(
ValueError,
match=
"The normal mode to local mode transformation matrix must be real"
):
in_state, t, U, w, ns, cf = d
dynamics.sample_fock(in_state, t, 1.0j * U, w, ns, cf)
def test_invalid_input_photon(self, d):
"""Test if function raises a ``ValueError`` when the number of photons in each input state
mode is not smaller than cutoff."""
with pytest.raises(
ValueError,
match=
"Number of photons in each input mode must be smaller than cutoff",
):
in_state, t, U, w, ns, cf = d
dynamics.sample_fock([i * 2 for i in in_state], t, U, w, ns, 3)
def test_invalid_mode(self, d):
"""Test if function raises a ``ValueError`` when the number of modes in the input state and
the normal-to-local transformation matrix are different."""
with pytest.raises(
ValueError,
match=
"Number of modes in the input state and the normal-to-local transformation",
):
in_state, t, U, w, ns, cf = d
dynamics.sample_fock(in_state + [0], t, U, w, ns, cf)
def test_rgate(self, monkeypatch, d):
"""Test if function correctly uses the rotation parameter in the rgates."""
if len(d[0]) == 2:
mock_eng_run = mock.MagicMock()
with monkeypatch.context() as m:
m.setattr(sf.LocalEngine, "run", mock_eng_run)
dynamics.sample_fock(*d)
p_func = mock_eng_run.call_args[0][0]
assert np.allclose(p_func.circuit[3].op.p, -7.374345193888777)
assert np.allclose(p_func.circuit[4].op.p, -7.13449983982334)
def test_loss(self, monkeypatch, d):
"""Test if function correctly creates the SF program for lossy circuits."""
def save_hist(*args):
call_history.append(args[1])
return sf.engine.Result
call_history = []
with monkeypatch.context() as m:
m.setattr(sf.engine.Result, "samples", np.array([[0]]))
m.setattr(sf.LocalEngine, "run", save_hist)
dynamics.sample_fock(*d, loss=0.5)
assert isinstance(call_history[0].circuit[-2].op, sf.ops.LossChannel)
def test_interferometer(self, monkeypatch, d):
"""Test if function correctly uses the interferometer unitaries."""
if len(d[0]) == 2:
mock_eng_run = mock.MagicMock()
with monkeypatch.context() as m:
m.setattr(sf.LocalEngine, "run", mock_eng_run)
dynamics.sample_fock(*d)
p_func = mock_eng_run.call_args[0][0]
_, _, U, _, _, _ = d
assert np.allclose(p_func.circuit[2].op.p, U.T)
assert np.allclose(p_func.circuit[5].op.p, U)
def test_op_order(self, monkeypatch, d):
"""Test if function correctly applies the operations."""
if len(d[0]) == 2:
mock_eng_run = mock.MagicMock()
with monkeypatch.context() as m:
m.setattr(sf.LocalEngine, "run", mock_eng_run)
dynamics.sample_fock(*d)
p_func = mock_eng_run.call_args[0][0]
assert isinstance(p_func.circuit[0].op, sf.ops.Fock)
assert isinstance(p_func.circuit[1].op, sf.ops.Fock)
assert isinstance(p_func.circuit[2].op, sf.ops.Interferometer)
assert isinstance(p_func.circuit[3].op, sf.ops.Rgate)
assert isinstance(p_func.circuit[4].op, sf.ops.Rgate)
assert isinstance(p_func.circuit[5].op, sf.ops.Interferometer)
assert isinstance(p_func.circuit[6].op, sf.ops.MeasureFock)
def test_fock_integration(d):
"""Integration test for the function ``strawberryfields.apps.qchem.dynamics.sample_fock`` to
check if it returns samples of correct form, i.e., correct number of samples, correct number of
modes, all non-negative integers."""
samples = np.array(dynamics.sample_fock(*d))
dims = samples.shape
assert len(dims) == 2
assert dims == (d[4], len(d[2]))
assert samples.dtype == "int"
assert (samples >= 0).all()
def test_invalid_time(self, d):
"""Test if function raises a ``ValueError`` when a negative time is given."""
with pytest.raises(ValueError, match="Time must be zero or positive"):
in_state, t, U, w, ns, cf = d
dynamics.sample_fock(in_state, -t, U, w, ns, cf)
