How to extract per shots measurement result from ionq device using qiskit_braket_provider?

Question

I'm running a circuit on ionq device using qiskit_braket_provider. I want to extract per shot measurement results. While running on IBMQ backends, it can be accessed by setting memory=True in execute function and then running job.result().get_memory(qc). I'm trying to similar thing for ionq device, but getting the following error.

Code:

job = ionq.run(tqc,shots=1024,memory=True)
job.status()
job.wait_for_final_state()
result = job.result()
m = job.result().get_memory(tqc)
print(m)

Error:

---------------------------------------------------------------------------
QiskitError                               Traceback (most recent call last)
Input In [70], in <cell line: 1>()
----> 1 m = job.result().get_memory(tqc)
      2 m
File ~/anaconda3/envs/qlab/lib/python3.10/site-packages/qiskit/result/result.py:217, in Result.get_memory(self, experiment)
    191 def get_memory(self, experiment=None):
    192     """Get the sequence of memory states (readouts) for each shot
    193     The data from the experiment is a list of format
    194     ['00000', '01000', '10100', '10100', '11101', '11100', '00101', ..., '01010']
   (...)
    215         QiskitError: if there is no memory data for the circuit.
    216     """
--> 217     exp_result = self._get_experiment(experiment)
    218     try:
    219         try:  # header is not available
File ~/anaconda3/envs/qlab/lib/python3.10/site-packages/qiskit/result/result.py:380, in Result._get_experiment(self, key)
    373 exp = [
    374     result
    375     for result in self.results
    376     if getattr(getattr(result, "header", None), "name", "") == key
    377 ]
    379 if len(exp) == 0:
--> 380     raise QiskitError('Data for experiment "%s" could not be found.' % key)
    381 if len(exp) == 1:
    382     exp = exp[0]
QiskitError: 'Data for experiment "circuit-7034" could not be found.'

One more thing, how to extract execution time for job on ionq device? In IBMQ simply job.result().time_taken returns it.

score 2 · Accepted Answer · answered Aug 18 '22 at 20:46

From what I can tell, this information isn't available from the provider because the header parameter isn't supplied to the ExperimentResult constructor. This might be worth submitting an issue or PR for!

In the meantime, you can get per-shot results by getting the Amazon Braket task result directly:

from braket.aws import AwsQuantumTask
task = AwsQuantumTask(job.job_id())
measurements = task.result().measurements

How to extract per shots measurement result from ionq device using qiskit_braket_provider?

1 Answers1