Error using FixedIncomeExpectedValue sample

Question

I am working with Aqua sample (qiskit-aqua/test/finance/test_readme_sample.py ) that uses the FixedIncomeExpectedValue and the AmplitudeEstimation.

It is qiskit 0.18

This sample was previously working with qiskit 0.16.2 when Statevector_simulator was used for AmplitudeEstimation. Though I used to run into an error ERROR_RUNNING_JOB when running on ibmq_ hardware. I was told to upgrade to qiskit 0.18 to fix that.

Since the update it now fails in _check_conflicting_argument with the message "The parameters pass_manager conflicts with the following parameter(s): backend." as shown below is a stack trace

    :
qc = compiler.transpile(circuit, BasicAer.get_backend('qasm_simulator'), pass_manager=p_m)

File "C:\Users\-----\Anaconda3\envs\qiskite\lib\site-packages\qiskit\compiler\transpile.py", line 188, in transpile
        routing_method=routing_method, backend=backend)

File "C:\Users\------\Anaconda3\envs\qiskite\lib\site-packages\qiskit\compiler\transpile.py", line 225, in _check_conflicting_argument
        "parameter(s): {}.".format(', '.join(conflicting_args)))

TranspilerError: 'The parameters pass_manager conflicts with the following parameter(s): backend.'

Further walk through the stack trace shows the following

bckend = set_backend('STATEVEC')

ampest = AmplitudeEstimation(m, fixed_income)
result = ampest.run(quantum_instance=bckend)
..quantum_algorithm.run()
....ae.run
......if _quantum_instance.is_statevector:
........construct_circuit(measurement = False)
..........pec = PhaseEstimationCircuit(...)
..........pec.construct_circuit(measurement = False)
............._state_n_circuit_factory(qc,q,aux)
................uncertainty_model.build(...) #fixed_income_....py
..................cs = Custom(...) #multivariate_distribution.py
..................extend(cs.construct_circuit('circuit',q))   
.....................cs.construct_circuit('circuit')
........................svc = StateVectorCircuit(_state_vector)
........................sv.construct_circuit(...)
..........................convert_to_basis_gates()
............................Unroller(...)
............................PassManager(...)
............................compiler.transpile(circuit, BasicAer.get_backend('qasm_simulator)...)
.............................. transpile (....)
................................._check_conflicting_argument(...backend=backend)

It is in this _check_conflicting_argument that the error message is raised "The parameters pass_manager conflicts with the following parameter(s): backend." and the script stops execution.

Please let me know what am I missing something here.

Thank you

Answer 1

The quick answer to your problem is to install Qiskit Aqua directly from GitHub instead of via pip. On the lastest master version, this bug is fixed. You can do this using

git clone https://github.com/Qiskit/qiskit-aqua
cd qiskit-aqua
pip install .

more detailed instructions are given on Qiskit's webpage.

As to why you're getting this error: This comes from a change in Qiskit Terra which resulted in an incompatibility with the current implementation in Qiskit Aqua. That was fixed in this commit on GitHub. This fix is in the master branch of the repository, however when you're installing via pip you're getting the last stable version, where this fix is not yet included. With the next release of Aqua (this will be 0.7.0) this bug is resolved in the pip version, too.