运行Qiskit VQE Alogrithum时的属性错误

Question

我试图使用Aer后端模拟器运行VQE算法。但是，每当我运行该算法时，我都会收到以下错误："AttributeError：'TwoLocal‘对象没有属性'set_max_evals_grouped'“

有人能解释一下这个错误意味着什么吗?我怎样才能修正它？

这是我正在使用的代码：

driver = PySCFDriver(atom='Li .0 .0 .0; H .0 .0 1.5049', unit=UnitsType.ANGSTROM, charge=0, spin=0, basis='sto3g')



#create  second quantiesed operator 
es_problem= ElectronicStructureProblem(driver)
seconded_quanitsied_oprator= es_problem.second_q_ops() 
print(seconded_quanitsied_oprator)



#convert to qubit operator 


qubit_transformation = QubitConverter(JordanWignerMapper())
qubit_operator = qubit_transformation.convert(seconded_quanitsied_oprator[0])
print(qubit_operator) 


#set up simulator 
backend = BasicAer.get_backend('statevector_simulator')
quantum_instance=QuantumInstance(backend=backend)

# VEQ algothiums 
groundstate_energies = []
classical_optimizer = SLSQP(maxiter = 1000)


ansatz = TwoLocal(rotation_blocks='ry', entanglement_blocks='cz')


Vqe = VQE(qubit_operator,ansatz,SLSQP,quantum_instance )

Answer 1

您正在使用VQE的旧方式(当它在Aqua)，所以它不再工作了。相反，你应该做的是：

vqe = VQE(ansatz = ansatz,
          optimizer = SLSQP, 
          quantum_instance=quantum_instance)
vqe_result = vqe.compute_minimum_eigenvalue(qubit_operator)

以防万一，您需要知道的关于如何从Aqua迁移的所有信息都可以在这里获得：https://qiskit.org/documentation/aqua_migration.html