cirq.estimate_parallel_single_qubit_readout_errors

Estimate single qubit readout error using parallel operations.

cirq.estimate_parallel_single_qubit_readout_errors(
    sampler: cirq.Sampler,
    *,
    qubits: Iterable[cirq.Qid],
    trials: int = 20,
    repetitions: int = 1000,
    trials_per_batch: (int | None) = None,
    bit_strings: (np.ndarray | None) = None
) -> SingleQubitReadoutCalibrationResult

Used in the notebooks

Used in the tutorials

For each trial, prepare and then measure a random computational basis bitstring on qubits using gates in parallel. Returns a SingleQubitReadoutCalibrationResult which can be used to compute readout errors for each qubit.

sampler The cirq.Sampler used to run the circuits.
qubits The qubits being tested.
repetitions The number of measurement repetitions to perform for each trial.
trials The number of bitstrings to prepare.
trials_per_batch If provided, split the experiment into batches with this number of trials in each batch.
bit_strings Optional numpy array of shape (trials, qubits) where the first dimension is the number of the trial and the second dimension is the qubit (ordered by the qubit order from the qubits parameter). Each value should be a 0 or 1 which specifies which state the qubit should be prepared into during that trial. If not provided, the function will generate random bit strings for you.

A SingleQubitReadoutCalibrationResult storing the readout error probabilities as well as the number of repetitions used to estimate the probabilities. Also stores a timestamp indicating the time when data was finished being collected from the sampler. Note that, if there did not exist a trial where a given qubit was set to |0〉, the zero-state error will be set to nan (not a number). Likewise for qubits with no |1〉trial and one-state error.

ValueError If the number of trials, repetitions, or trials_per batch is negative, or if bit_strings is not a numpy array or of the wrong shape.