qiskit.ignis.mitigation.CompleteMeasFitter¶

class CompleteMeasFitter(results, state_labels, qubit_list=None, circlabel='')[source]¶

Measurement correction fitter for a full calibration

Initialize a measurement calibration matrix from the results of running the circuits returned by measurement_calibration_circuits

A wrapper for the tensored fitter

Parameters

results (Union[Result, List[Result]]) – the results of running the measurement calibration circuits. If this is None the user will set a calibration matrix later.
state_labels (List[str]) – list of calibration state labels returned from measurement_calibration_circuits. The output matrix will obey this ordering.
qubit_list (Optional[List[int]]) – List of the qubits (for reference and if the subset is needed). If None, the qubit_list will be created according to the length of state_labels[0].
circlabel (str) – if the qubits were labeled.

__init__(results, state_labels, qubit_list=None, circlabel='')[source]¶

Initialize a measurement calibration matrix from the results of running the circuits returned by measurement_calibration_circuits

A wrapper for the tensored fitter

Parameters

results (Union[Result, List[Result]]) – the results of running the measurement calibration circuits. If this is None the user will set a calibration matrix later.
state_labels (List[str]) – list of calibration state labels returned from measurement_calibration_circuits. The output matrix will obey this ordering.
qubit_list (Optional[List[int]]) – List of the qubits (for reference and if the subset is needed). If None, the qubit_list will be created according to the length of state_labels[0].
circlabel (str) – if the qubits were labeled.

Methods

`__init__`(results, state_labels[, …])	Initialize a measurement calibration matrix from the results of running the circuits returned by measurement_calibration_circuits
`add_data`(new_results[, rebuild_cal_matrix])	Add measurement calibration data
`plot_calibration`([ax, show_plot])	Plot the calibration matrix (2D color grid plot)
`readout_fidelity`([label_list])	Based on the results, output the readout fidelity which is the normalized trace of the calibration matrix
`subset_fitter`([qubit_sublist])	Return a fitter object that is a subset of the qubits in the original list.

Attributes

`cal_matrix`	Return cal_matrix.
`filter`	Return a measurement filter using the cal matrix.
`qubit_list`	Return list of qubits.
`state_labels`	Return state_labels.

add_data(new_results, rebuild_cal_matrix=True)[source]¶

Add measurement calibration data

Parameters

new_results (list or qiskit.result.Result) – a single result or list of result objects.
rebuild_cal_matrix (bool) – rebuild the calibration matrix

plot_calibration(ax=None, show_plot=True)[source]¶

Plot the calibration matrix (2D color grid plot)

Parameters

readout_fidelity(label_list=None)[source]¶

Based on the results, output the readout fidelity which is the normalized trace of the calibration matrix

Parameters: label_list (bool) – If None, returns the average assignment fidelity of a single state. Otherwise it returns the assignment fidelity to be in any one of these states averaged over the second index.
Returns: readout fidelity (assignment fidelity)
Return type: numpy.array

Additional Information:: The on-diagonal elements of the calibration matrix are the probabilities of measuring state ‘x’ given preparation of state ‘x’ and so the normalized trace is the average assignment fidelity

subset_fitter(qubit_sublist=None)[source]¶

Return a fitter object that is a subset of the qubits in the original list.

Parameters

qubit_sublist (list) – must be a subset of qubit_list

Returns

Return type

CompleteMeasFitter

Raises

QiskitError – If the calibration matrix is not initialized