def test_produces_samples():
a, b = cirq.LineQubit.range(2)
c = cirq.Circuit(cirq.H(a), cirq.CNOT(a, b), cirq.measure(a, key='a'),
cirq.measure(b, key='b'))
result = cirq.StabilizerSampler().sample(c, repetitions=100)
assert 5 < sum(result['a']) < 95
assert np.all(result['a'] ^ result['b'] == 0)
def test_stabilizer_supports_depolarize():
with pytest.raises(TypeError, match="act_on"):
for _ in range(100):
cirq.act_on(cirq.depolarize(3 / 4), object())
q = cirq.LineQubit(0)
c = cirq.Circuit(cirq.depolarize(3 / 4).on(q), cirq.measure(q, key='m'))
m = np.sum(cirq.StabilizerSampler().sample(c, repetitions=100)['m'])
assert 5 < m < 95
def test_reset():
q = cirq.LineQubit(0)
sampler = cirq.StabilizerSampler()
c = cirq.Circuit(cirq.X(q), cirq.reset(q), cirq.measure(q))
assert sampler.sample(c)['q(0)'][0] == 0
c = cirq.Circuit(cirq.H(q), cirq.reset(q), cirq.measure(q))
assert sampler.sample(c)['q(0)'][0] == 0
c = cirq.Circuit(cirq.reset(q), cirq.measure(q))
assert sampler.sample(c)['q(0)'][0] == 0
def test_unsupported_stabilizer_safety():
with pytest.raises(TypeError, match="act_on"):
for _ in range(100):
cirq.act_on(cirq.X.with_probability(0.5), object())
with pytest.raises(TypeError, match="act_on"):
cirq.act_on(cirq.X.with_probability(sympy.Symbol('x')), object())
q = cirq.LineQubit(0)
c = cirq.Circuit((cirq.X(q)**0.25).with_probability(0.5),
cirq.measure(q, key='m'))
with pytest.raises(TypeError, match='Failed to act'):
cirq.StabilizerSampler().sample(c, repetitions=100)
def test_unsupported_stabilizer_safety():
from cirq.protocols.act_on_protocol_test import DummySimulationState
with pytest.raises(TypeError, match="act_on"):
for _ in range(100):
cirq.act_on(cirq.X.with_probability(0.5),
DummySimulationState(),
qubits=())
with pytest.raises(TypeError, match="act_on"):
cirq.act_on(cirq.X.with_probability(sympy.Symbol('x')),
DummySimulationState(),
qubits=())
q = cirq.LineQubit(0)
c = cirq.Circuit((cirq.X(q)**0.25).with_probability(0.5),
cirq.measure(q, key='m'))
with pytest.raises(TypeError, match='Failed to act'):
cirq.StabilizerSampler().sample(c, repetitions=100)
def test_stabilizer_supports_probability():
q = cirq.LineQubit(0)
c = cirq.Circuit(cirq.X(q).with_probability(0.5), cirq.measure(q, key='m'))
m = np.sum(cirq.StabilizerSampler().sample(c, repetitions=100)['m'])
assert 5 < m < 95
