def test_run_parameters_not_resolved():
a = cirq.LineQubit(0)
simulator = cirq.MPSSimulator()
circuit = cirq.Circuit(
cirq.XPowGate(exponent=sympy.Symbol('a'))(a), cirq.measure(a))
with pytest.raises(ValueError, match='symbols were not specified'):
_ = simulator.run_sweep(circuit, cirq.ParamResolver({}))
def test_sample_seed():
q = cirq.NamedQubit('q')
circuit = cirq.Circuit(cirq.H(q), cirq.measure(q))
simulator = cirq.MPSSimulator(seed=1234)
result = simulator.run(circuit, repetitions=20)
measured = result.measurements['q']
result_string = ''.join(map(lambda x: str(int(x[0])), measured))
assert result_string == '01011001110111011011'
def test_measurement_str():
q0 = cirq.NamedQid('q0', dimension=3)
circuit = cirq.Circuit(cirq.measure(q0))
simulator = cirq.MPSSimulator()
result = simulator.run(circuit, repetitions=7)
assert str(result) == "q0 (d=3)=0000000"
def test_measurement():
q0, q1 = cirq.LineQubit.range(2)
circuit = cirq.Circuit(cirq.X(q0), cirq.H(q1), cirq.measure(q1))
simulator = cirq.MPSSimulator()
result = simulator.run(circuit, repetitions=100)
assert sum(result.measurements['1'])[0] < 80
assert sum(result.measurements['1'])[0] > 20
def test_state_copy():
sim = cirq.MPSSimulator()
q = cirq.LineQubit(0)
circuit = cirq.Circuit(cirq.H(q), cirq.H(q))
state_Ms = []
for step in sim.simulate_moment_steps(circuit):
state_Ms.append(step.state.M)
for x, y in itertools.combinations(state_Ms, 2):
assert len(x) == len(y)
for i in range(len(x)):
assert not np.shares_memory(x[i], y[i])
def assert_same_output_as_dense(circuit, qubit_order, initial_state=0):
mps_simulator = cirq.MPSSimulator()
ref_simulator = cirq.Simulator()
actual = mps_simulator.simulate(circuit,
qubit_order=qubit_order,
initial_state=initial_state)
expected = ref_simulator.simulate(circuit,
qubit_order=qubit_order,
initial_state=initial_state)
np.testing.assert_almost_equal(actual.final_state.to_numpy(),
expected.final_state_vector)
assert len(actual.measurements) == 0
def test_simulate_moment_steps_sample():
q0, q1 = cirq.LineQubit.range(2)
circuit = cirq.Circuit(cirq.H(q0), cirq.CNOT(q0, q1))
simulator = cirq.MPSSimulator()
for i, step in enumerate(simulator.simulate_moment_steps(circuit)):
if i == 0:
np.testing.assert_almost_equal(
step._simulator_state().to_numpy(),
np.asarray([1.0 / math.sqrt(2), 0.0, 1.0 / math.sqrt(2), 0.0]),
)
assert str(
step
) == "[array([[[0.70710678+0.j, 0.70710678+0.j]]]), array([[[1., 0.]]])]"
samples = step.sample([q0, q1], repetitions=10)
for sample in samples:
assert np.array_equal(sample, [True, False]) or np.array_equal(
sample, [False, False])
np.testing.assert_almost_equal(
step._simulator_state().to_numpy(),
np.asarray([1.0 / math.sqrt(2), 0.0, 1.0 / math.sqrt(2), 0.0]),
)
else:
np.testing.assert_almost_equal(
step._simulator_state().to_numpy(),
np.asarray([1.0 / math.sqrt(2), 0.0, 0.0, 1.0 / math.sqrt(2)]),
)
assert (str(step) == """[array([[[0.84089642+0.j, 0. +0.j],
[0. +0.j, 0.84089642+0.j]]]), array([[[0.84089642+0.j, 0. +0.j]],
[[0. +0.j, 0.84089642+0.j]]])]""")
samples = step.sample([q0, q1], repetitions=10)
for sample in samples:
assert np.array_equal(sample, [True, True]) or np.array_equal(
sample, [False, False])
def test_run_no_repetitions():
q0 = cirq.LineQubit(0)
simulator = cirq.MPSSimulator()
circuit = cirq.Circuit(cirq.H(q0), cirq.measure(q0))
result = simulator.run(circuit, repetitions=0)
assert len(result.measurements['0']) == 0