def test_R_operator_with_hand_calc_example_1_qubit():
# This example was worked out by hand
rho = ID / 2
obs_freqs = [3, 7]
my_by_hand_calc_ans_Z = ((3 / 0.5) * PROJ_ZERO +
(7 / 0.5) * PROJ_ONE) / sum(obs_freqs)
my_by_hand_calc_ans_X = ((3 / 0.5) * PROJ_PLUS +
(7 / 0.5) * PROJ_MINUS) / sum(obs_freqs)
qubits = [Q0]
exp = (obs_freqs[0] - obs_freqs[1]) / sum(obs_freqs)
zplus_result = ExperimentResult(setting=Z_SETTING,
expectation=exp,
total_counts=sum(obs_freqs))
xplus_result = ExperimentResult(setting=X_SETTING,
expectation=exp,
total_counts=sum(obs_freqs))
z_results = [zplus_result]
x_results = [xplus_result]
# Z basis test
np.testing.assert_allclose(_R(rho, z_results, qubits),
my_by_hand_calc_ans_Z,
atol=1e-12)
# X basis test
np.testing.assert_allclose(_R(rho, x_results, qubits),
my_by_hand_calc_ans_X,
atol=1e-12)
def test_R_operator_fixed_point_2_qubit():
# Check fixed point of operator. See Eq. 5 in Řeháček et al., PRA 75, 042108 (2007).
obs_freqs = [1, 0, 0, 0]
# Z basis test
actual = np.trace(
_R(P00, ZZ_EFFECTS, obs_freqs) @ P00 @ _R(P00, ZZ_EFFECTS, obs_freqs) -
P00)
np.testing.assert_allclose(actual, 0.0, atol=1e-12)
def test_R_operator_with_hand_calc_example_1_qubit():
# This example was worked out by hand
rho = ID / 2
obs_freqs = [3, 7]
my_by_hand_calc_ans_Z = ((3 / 0.5) * PROJ_ZERO + (7 / 0.5) * PROJ_ONE) / np.sum(obs_freqs)
my_by_hand_calc_ans_X = ((3 / 0.5) * PROJ_PLUS + (7 / 0.5) * PROJ_MINUS) / np.sum(obs_freqs)
# Z basis test
assert np.trace(_R(rho, Z_EFFECTS, obs_freqs / np.sum(obs_freqs)) - my_by_hand_calc_ans_Z) == 0
# X basis test
assert np.trace(_R(rho, X_EFFECTS, obs_freqs / np.sum(obs_freqs)) - my_by_hand_calc_ans_X) == 0
def test_R_operator_fixed_point_2_qubit():
# Check fixed point of operator. See Eq. 5 in Řeháček et al., PRA 75, 042108 (2007).
qubits = [0, 1]
id_setting = ExperimentSetting(in_state=zeros_state(qubits), observable=sI(qubits[0])*sI(
qubits[1]))
zz_setting = ExperimentSetting(in_state=zeros_state(qubits), observable=sZ(qubits[0])*sI(
qubits[1]))
id_result = ExperimentResult(setting=id_setting, expectation=1, total_counts=1)
zzplus_result = ExperimentResult(setting=zz_setting, expectation=1, total_counts=1)
zz_results = [id_result, zzplus_result]
# Z basis test
r = _R(P00, zz_results, qubits)
actual = r @ P00 @ r
np.testing.assert_allclose(actual, P00, atol=1e-12)
def test_trace(rho, effects):
return np.trace(
_R(rho, effects, obs_freqs) @ rho @ _R(rho, effects, obs_freqs) -
rho)
def test_trace(rho, results):
return _R(rho, results, qubits) @ rho @ _R(rho, results, qubits)