def test_measure_state_no_indices_out_is_state():
initial_state = cirq.to_valid_state_vector(0, 3)
bits, state = cirq.measure_state_vector(initial_state, [],
out=initial_state)
assert [] == bits
np.testing.assert_almost_equal(state, initial_state)
assert state is initial_state
def test_measure_state_partial_indices():
for index in range(3):
for x in range(8):
initial_state = cirq.to_valid_state_vector(x, 3)
bits, state = cirq.measure_state_vector(initial_state, [index])
np.testing.assert_almost_equal(state, initial_state)
assert bits == [bool(1 & (x >> (2 - index)))]
def test_measure_state_partial_indices_all_orders():
for perm in itertools.permutations([0, 1, 2]):
for x in range(8):
initial_state = cirq.to_valid_state_vector(x, 3)
bits, state = cirq.measure_state_vector(initial_state, perm)
np.testing.assert_almost_equal(state, initial_state)
assert bits == [bool(1 & (x >> (2 - p))) for p in perm]
def test_deprecated():
with cirq.testing.assert_logs('cirq.bloch_vector_from_state_vector',
'deprecated'):
_ = cirq.sim.bloch_vector_from_state_vector(np.array([1, 0]), 0)
with cirq.testing.assert_logs('cirq.density_matrix_from_state_vector',
'deprecated'):
_ = cirq.sim.density_matrix_from_state_vector(np.array([1, 0]))
with cirq.testing.assert_logs('cirq.dirac_notation', 'deprecated'):
_ = cirq.sim.dirac_notation(np.array([1, 0]))
with cirq.testing.assert_logs('cirq.to_valid_state_vector', 'deprecated'):
_ = cirq.sim.to_valid_state_vector(0, 1)
with cirq.testing.assert_logs('irq.validate_normalized_state',
'deprecated'):
_ = cirq.sim.validate_normalized_state(np.array([1, 0],
dtype=np.complex64),
qid_shape=(2, ))
with cirq.testing.assert_logs('cirq.STATE_VECTOR_LIKE', 'deprecated'):
# Reason for type: ignore: https://github.com/python/mypy/issues/5354
_ = cirq.sim.STATE_VECTOR_LIKE # type: ignore
state_vector = np.array([1, 1]) / np.sqrt(2)
with cirq.testing.assert_logs('state', 'state_vector', 'deprecated'):
# pylint: disable=unexpected-keyword-arg,no-value-for-parameter
_ = cirq.sample_state_vector(state=state_vector, indices=[0])
with cirq.testing.assert_logs('state', 'state_vector', 'deprecated'):
# pylint: disable=unexpected-keyword-arg,no-value-for-parameter
_ = cirq.measure_state_vector(state=state_vector, indices=[0])
def test_measure_state_no_indices_out_is_not_state():
initial_state = cirq.to_valid_state_vector(0, 3)
out = np.zeros_like(initial_state)
bits, state = cirq.measure_state_vector(initial_state, [], out=out)
assert [] == bits
np.testing.assert_almost_equal(state, initial_state)
assert state is out
assert out is not initial_state
def test_measure_state_out_is_not_state():
initial_state = np.zeros(8, dtype=np.complex64)
initial_state[0] = 1 / np.sqrt(2)
initial_state[2] = 1 / np.sqrt(2)
out = np.zeros_like(initial_state)
_, state = cirq.measure_state_vector(initial_state, [2, 1, 0], out=out)
assert out is not initial_state
assert out is state
def test_measure_state_seed():
n = 10
initial_state = np.ones(2**n) / 2**(n / 2)
bits, state1 = cirq.measure_state_vector(initial_state, range(n), seed=1234)
np.testing.assert_equal(
bits,
[False, False, True, True, False, False, False, True, False, False])
bits, state2 = cirq.measure_state_vector(initial_state,
range(n),
seed=np.random.RandomState(1234))
np.testing.assert_equal(
bits,
[False, False, True, True, False, False, False, True, False, False])
np.testing.assert_allclose(state1, state2)
def test_measure_state_out_is_state():
initial_state = np.zeros(8, dtype=np.complex64)
initial_state[0] = 1 / np.sqrt(2)
initial_state[2] = 1 / np.sqrt(2)
bits, state = cirq.measure_state_vector(initial_state, [2, 1, 0], out=initial_state)
expected = np.zeros(8, dtype=np.complex64)
expected[2 if bits[1] else 0] = 1.0
np.testing.assert_array_almost_equal(initial_state, expected)
assert state is initial_state
def test_measure_state_reshape():
results = []
for x in range(8):
initial_state = np.reshape(cirq.to_valid_state_vector(x, 3), [2] * 3)
bits, state = cirq.measure_state_vector(initial_state, [2, 1, 0])
results.append(bits)
np.testing.assert_almost_equal(state, initial_state)
expected = [list(reversed(x)) for x in list(itertools.product([False, True], repeat=3))]
assert results == expected
def test_measure_state_collapse():
initial_state = np.zeros(8, dtype=np.complex64)
initial_state[0] = 1 / np.sqrt(2)
initial_state[2] = 1 / np.sqrt(2)
for _ in range(10):
bits, state = cirq.measure_state_vector(initial_state, [2, 1, 0])
assert bits in [[False, False, False], [False, True, False]]
expected = np.zeros(8, dtype=np.complex64)
expected[2 if bits[1] else 0] = 1.0
np.testing.assert_almost_equal(state, expected)
assert state is not initial_state
# Partial sample is correct.
for _ in range(10):
bits, state = cirq.measure_state_vector(initial_state, [2])
np.testing.assert_almost_equal(state, initial_state)
assert bits == [False]
bits, state = cirq.measure_state_vector(initial_state, [0])
np.testing.assert_almost_equal(state, initial_state)
assert bits == [False]
def test_measure_state_empty_state():
initial_state = np.array([1.0])
bits, state = cirq.measure_state_vector(initial_state, [])
assert [] == bits
np.testing.assert_almost_equal(state, initial_state)
def test_measure_state_index_out_of_range():
state = cirq.to_valid_state_vector(0, 3)
with pytest.raises(IndexError, match='-2'):
cirq.measure_state_vector(state, [-2])
with pytest.raises(IndexError, match='3'):
cirq.measure_state_vector(state, [3])
def test_measure_state_not_power_of_two():
with pytest.raises(ValueError, match='3'):
_, _ = cirq.measure_state_vector(np.array([1, 0, 0]), [1])
with pytest.raises(ValueError, match='5'):
cirq.measure_state_vector(np.array([0, 1, 0, 0, 0]), [1])
def test_measure_state_partial_indices_order():
for x in range(8):
initial_state = cirq.to_valid_state_vector(x, 3)
bits, state = cirq.measure_state_vector(initial_state, [2, 1])
np.testing.assert_almost_equal(state, initial_state)
assert bits == [bool(1 & (x >> 0)), bool(1 & (x >> 1))]
