def test_sandwich_operator_identity():
qubits = cirq.LineQubit.range(6)
circuit = cirq.testing.random_circuit(qubits=qubits,
n_moments=10,
op_density=0.8)
tot_c = ccq.circuit_for_expectation_value(circuit, cirq.PauliString({}))
np.testing.assert_allclose(cirq.unitary(tot_c),
np.eye(2**len(qubits)),
atol=1e-6)
def test_tensor_unitary():
rs = np.random.RandomState(52)
for _ in range(10):
qubits = cirq.LineQubit.range(5)
circuit = cirq.testing.random_circuit(
qubits=qubits, n_moments=10, op_density=0.8, random_state=rs
)
operator = _random_pauli_string(qubits, rs)
circuit_sand = ccq.circuit_for_expectation_value(circuit, operator)
u_tn = ccq.tensor_unitary(circuit_sand, qubits)
u_cirq = cirq.unitary(circuit_sand)
np.testing.assert_allclose(u_tn, u_cirq, atol=1e-6)
def test_sandwich_operator_expect_val():
rs = np.random.RandomState(52)
qubits = cirq.LineQubit.range(5)
for _ in range(10): # try a bunch of different ones
circuit = cirq.testing.random_circuit(
qubits=qubits, n_moments=10, op_density=0.8, random_state=rs
)
operator = _random_pauli_string(qubits, rs)
tot_c = ccq.circuit_for_expectation_value(circuit, operator)
eval_sandwich = cirq.unitary(tot_c)[0, 0]
wfn = cirq.Simulator().simulate(circuit)
eval_normal = operator.expectation_from_state_vector(wfn.final_state_vector, wfn.qubit_map)
np.testing.assert_allclose(eval_sandwich, eval_normal, atol=1e-5)
def test_circuit_to_tensors(simplify):
rs = np.random.RandomState(52)
qubits = cirq.LineQubit.range(2)
circuit = cirq.testing.random_circuit(qubits=qubits,
n_moments=10,
op_density=0.8)
operator = cirq.PauliString(
{q: cirq.Z for q in rs.choice(qubits, size=2, replace=False)})
circuit_sand = ccq.circuit_for_expectation_value(circuit, operator)
if simplify:
ccq.simplify_expectation_value_circuit(circuit_sand)
qubits = sorted(circuit_sand.all_qubits())
u_tn = ccq.tensor_unitary(circuit=circuit_sand, qubits=qubits)
u_cirq = cirq.unitary(circuit_sand)
np.testing.assert_allclose(u_tn, u_cirq, atol=1e-6)
def test_simplify_sandwich():
rs = np.random.RandomState(52)
for width in [2, 3]:
for height in [1, 3]:
for p in [1, 2]:
circuit, qubits = _get_circuit(width=width,
height=height,
p=p,
rs=rs)
operator = cirq.PauliString({
q: cirq.Z for q in rs.choice(qubits, size=2, replace=False)
})
tot_c = ccq.circuit_for_expectation_value(circuit, operator)
tot_c_init = tot_c.copy()
ccq.simplify_expectation_value_circuit(tot_c)
assert len(list(tot_c.all_operations())) < len(
list(tot_c_init.all_operations()))
np.testing.assert_allclose(
tot_c.unitary(qubit_order=qubits),
tot_c_init.unitary(qubit_order=qubits),
atol=1e-5)
