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---------------------------------------------------------------------------
JSONDecodeError                           Traceback (most recent call last)
<ipython-input-17-16f293a93614> in <module>
----> 1 arm_result = backend.run(rabi_qobj).result()

JSONDecodeError: Expecting value: line 1 column 1 (char 0)

---------------------------------------------------------------------------
JSONDecodeError                           Traceback (most recent call last)
<ipython-input-17-16f293a93614> in <module>
----> 1 result = backend.run(rabi_qobj).result()

JSONDecodeError: Expecting value: line 1 column 1 (char 0)

I'm trying to follow tutorial on pulse simulation described in qiskit.org. The generated PulseQobj is well executed with AER simulator, but it throws JSONDecodeError when using real backends (ex. ibmq-armonk). The PulseQobj passed the validation (validate_qobj_against_schema), so I'm struggling to find the reason.

I connected to real device with APItoken, and qiskit version is up to date (qiskit 0.22.0). Below is the log after backend.run(PulseQobj)

---------------------------------------------------------------------------
JSONDecodeError                           Traceback (most recent call last)
<ipython-input-17-16f293a93614> in <module>
----> 1 arm_result = backend.run(rabi_qobj).result()

D:\Anaconda3\lib\site-packages\qiskit\providers\ibmq\ibmqbackend.py in run(self, qobj, job_name, job_share_level, job_tags, validate_qobj)
    175         if validate_qobj:
    176             validate_qobj_against_schema(qobj)
--> 177         return self._submit_job(qobj, job_name, api_job_share_level, job_tags)
    178 
    179     def _submit_job(

D:\Anaconda3\lib\site-packages\qiskit\providers\ibmq\ibmqbackend.py in _submit_job(self, qobj, job_name, job_share_level, job_tags)
    213         try:
    214             qobj_dict = qobj.to_dict()
--> 215             submit_info = self._api_client.job_submit(
    216                 backend_name=self.name(),
    217                 qobj_dict=qobj_dict,

D:\Anaconda3\lib\site-packages\qiskit\providers\ibmq\api\clients\account.py in job_submit(self, backend_name, qobj_dict, job_name, job_share_level, job_tags)
    217 
    218         # Upload the Qobj to object storage.
--> 219         _ = job_api.put_object_storage(upload_url, qobj_dict)
    220 
    221         # Notify the API via the callback.

D:\Anaconda3\lib\site-packages\qiskit\providers\ibmq\api\rest\job.py in put_object_storage(self, url, qobj_dict)
    188         data = json.dumps(qobj_dict, cls=json_encoder.IQXJsonEncoder)
    189         logger.debug('Uploading to object storage.')
--> 190         response = self.session.put(url, data=data, bare=True, timeout=600,
    191                                     headers={'Content-Type': 'application/json'})
    192         return response.text

D:\Anaconda3\lib\site-packages\requests\sessions.py in put(self, url, data, **kwargs)
    588         """
    589 
--> 590         return self.request('PUT', url, data=data, **kwargs)
    591 
    592     def patch(self, url, data=None, **kwargs):

D:\Anaconda3\lib\site-packages\qiskit\providers\ibmq\api\session.py in request(self, method, url, bare, **kwargs)
    284                 except (ValueError, KeyError):
    285                     # the response did not contain the expected json.
--> 286                     message += ". {}".format(ex.response.json())
    287 
     288             if self.access_token:

D:\Anaconda3\lib\site-packages\requests\models.py in json(self, **kwargs)
    896                     # used.
    897                     pass
--> 898         return complexjson.loads(self.text, **kwargs)
    899 
    900     @property

D:\Anaconda3\lib\json\__init__.py in loads(s, cls, object_hook, parse_float, parse_int, parse_constant, object_pairs_hook, **kw)
    355             parse_int is None and parse_float is None and
    356             parse_constant is None and object_pairs_hook is None and not kw):
--> 357         return _default_decoder.decode(s)
    358     if cls is None:
    359         cls = JSONDecoder

D:\Anaconda3\lib\json\decoder.py in decode(self, s, _w)
    335 
    336         """
--> 337         obj, end = self.raw_decode(s, idx=_w(s, 0).end())
    338         end = _w(s, end).end()
    339         if end != len(s):

D:\Anaconda3\lib\json\decoder.py in raw_decode(self, s, idx)
    353             obj, end = self.scan_once(s, idx)
    354         except StopIteration as err:
--> 355             raise JSONDecodeError("Expecting value", s, err.value) from None
    356         return obj, end

JSONDecodeError: Expecting value: line 1 column 1 (char 0)

I'm trying to follow tutorial on pulse simulation described in qiskit.org. The generated PulseQobj is well executed with AER simulator, but it throws JSONDecodeError when using real backends (ex. ibmq-armonk). The PulseQobj passed the validation (validate_qobj_against_schema), so I'm struggling to find the reason. Qobj, generated by QuantumCircuit command, does not raise this error.

I connected to real device with APItoken, and qiskit version is up to date (qiskit 0.22.0). Below is the trial code with real device, and log after backend.run(PulseQobj)

%matplotlib inline

import numpy as np
from qiskit.ignis.characterization.calibrations import rabi_schedules, RabiFitter
from qiskit.pulse import DriveChannel
from qiskit.compiler import assemble
from qiskit.qobj.utils import MeasLevel, MeasReturnType
from qiskit import IBMQ

IBMQ.enable_account(APItoken, proxies = ProxyConfig, verify = certPath)
provider = IBMQ.get_provider(hub=hub, group=group, project=project)
backend = provider.get_backend(device)

# qubit list
qubits = [0]

# drive amplitudes to use
num_exps = 64
drive_amps = np.linspace(0, 1.0, num_exps) 

# drive shape parameters
drive_duration = 2048
drive_sigma = 256

# list of drive channels
drive_channels = [DriveChannel(0)]

# construct the schedules
rabi_schedules, xdata = rabi_schedules(amp_list=drive_amps, 
                                       qubits=qubits, 
                                       pulse_width=drive_duration, 
                                       pulse_sigma=drive_sigma,
                                       drives=drive_channels,  
                                       inst_map=backend.defaults().instruction_schedule_map, 
                                       meas_map=backend.configuration().meas_map)

rabi_qobj = assemble(rabi_schedules, 
                     backend=backend,
                     meas_level=1, 
                     meas_return='avg',
                     shots=512)

result = backend.run(rabi_qobj).result()

---------------------------------------------------------------------------
JSONDecodeError                           Traceback (most recent call last)
<ipython-input-17-16f293a93614> in <module>
----> 1 arm_result = backend.run(rabi_qobj).result()

JSONDecodeError: Expecting value: line 1 column 1 (char 0)