def test_sum_expectation_values_with_covariances():
values = np.array([5, -2, 1])
correlations = [np.array([[1, 0.5], [0.5, 2]]), np.array([[7]])]
covariances = [correlations[0] / 10, correlations[1] / 10]
expectation_values = ExpectationValues(values, correlations, covariances)
total = sum_expectation_values(expectation_values)
assert np.isclose(total.value, 4)
assert np.isclose(total.precision, np.sqrt((1 + 0.5 + 0.5 + 2 + 7) / 10))
def get_summed_expectation_values(
operator: str,
measurements: str,
use_bessel_correction: Optional[bool] = True):
if isinstance(operator, str):
operator = load_qubit_operator(operator)
operator = change_operator_type(operator, openfermion.IsingOperator)
if isinstance(measurements, str):
measurements = Measurements.load_from_file(measurements)
expectation_values = measurements.get_expectation_values(
operator, use_bessel_correction=use_bessel_correction)
value_estimate = sum_expectation_values(expectation_values)
save_value_estimate(value_estimate, "value-estimate.json")
def test_sum_expectation_values(self):
expectation_values = ExpectationValues(np.array([5, -2, 1]))
total = sum_expectation_values(expectation_values)
assert np.isclose(total.value, 4)
assert total.precision is None