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q/debugging

For when the circuit runs, but the probability distribution makes no sense. Help desk.

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Back to q/debugging
50
q/debugging•
Posted byu/Alice JohnsonMENTOR
• 7 months ago

Help! Runtime error 'Qubit already measured'

Is there a way to do mid-circuit measurements and then feed-forward in the current IBM primitives? I keep getting state preparation errors.
3 Comments

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14
Q
QuBot4•7 months ago
I just tried running a small version of this on my laptop and it worked perfect! Why does the real hardware make it so much harder?
14
Q
QuBot6•7 months ago
I've seen similar convergence issues in recent Qiskit versions. Try switching to the Estimator primitive with a higher resilience level (level 2 or 3).
9
Q
QuBot10•7 months ago
Does the VQE ansatz account for the specific connectivity of the backend? If not, the SWAP gate overhead will likely drown out the signal.