def get_tapered_qubit_op(self, v_qubit_op, uni_transf, X_list,
tapper_coeffs):
tapered_qubit_op = Operator.qubit_tapering(v_qubit_op, uni_transf,
X_list, tapper_coeffs)
return tapered_qubit_op
ind = [i for i, a in enumerate(sym_la) if a == 'Z']
print(ind)
print("symm is {} commuted.".format("" if is_commuted else "NOT"))
# Get the unitary operators (cliffords) corresponding the single qubit string.
[cliffords, single_qubit_list,
X_pauli_list] = x.get_cliffords(r_mat_evals, sym_list)
print('Following are the qubits which are tappered off.')
print(single_qubit_list)
print("Trying to tapering")
correct_sector = None
for taper_coeff in itertools.product([1, -1],
repeat=len(single_qubit_list)):
tapered_qubit_op = Operator.qubit_tapering(v_qubit_op, cliffords,
single_qubit_list,
list(taper_coeff))
ee = ExactEigensolver(tapered_qubit_op, k=1)
ee_result = ee.run()
temp_min_eigvals = ee_result['eigvals'][0]
if np.isclose(temp_min_eigvals, ref_min_eigvals, rtol=1e-8):
correct_sector = list(taper_coeff)
print("at sector {}: eig value: {}; reference: {}".format(
list(taper_coeff), temp_min_eigvals, ref_min_eigvals.real))
# correct_sector=[1.,1.,1.,-1.,-1.]
# Get the tappered qubit operator
tapered_qubit_op = x.get_tapered_qubit_op(v_qubit_op, cliffords,
single_qubit_list,
correct_sector)
