qiskit.ignis.verification.InterleavedRBFitter

class InterleavedRBFitter(original_result, interleaved_result, cliff_lengths, rb_pattern=None)

Class for fitters for interleaved RB, derived from RBFitterBase class.

Contains two RBFitter objects: the original RBFitter and the interleaved RBFitter.

Parameters

• original_result (list) – list of results of the original RB sequence (qiskit.Result).

• interleaved_result (list) – list of results of the interleaved RB sequence (qiskit.Result).

• cliff_lengths (list) – the Clifford lengths, 2D list i x j where i is the number of patterns, j is the number of cliffords lengths.

• rb_pattern (list) – the pattern for the RB sequences.

__init__(original_result, interleaved_result, cliff_lengths, rb_pattern=None)

Parameters

• original_result (list) – list of results of the original RB sequence (qiskit.Result).

• interleaved_result (list) – list of results of the interleaved RB sequence (qiskit.Result).

• cliff_lengths (list) – the Clifford lengths, 2D list i x j where i is the number of patterns, j is the number of cliffords lengths.

• rb_pattern (list) – the pattern for the RB sequences.

Methods

__init__(original_result, …[, rb_pattern])	param original_result list of results of the
add_data(new_original_result, …[, rerun_fit])	Add a new result.
calc_data()	Retrieve probabilities of success from execution results.
calc_statistics()	Extract averages and std dev.
fit_data()	Fit the interleaved RB results.
fit_data_pattern(patt_ind, fit_guess[, …])	Fit the RB results of a particular pattern to an exponential curve.
plot_rb_data([pattern_index, ax, add_label, …])	Plot interleaved randomized benchmarking data of a single pattern.

Attributes

cliff_lengths	Return clifford lengths.
fit	Return fit as a 2 element list.
fit_int	Return interleaved fit parameters.
raw_data	Return raw_data as a 2 element list.
rb_fit_fun	Return the fit function rb_fit_fun.
rbfit_int	Return the interleaved RB fitter.
rbfit_std	Return the original RB fitter.
results	Return all the results as a 2 element list.
seeds	Return the number of loaded seeds as a 2 element list.
ydata	Return ydata (means and std devs) as a 2 element list.

add_data(new_original_result, new_interleaved_result, rerun_fit=True)

Add a new result.

Parameters

• new_original_result (list) – list of RB results of the original circuits.

• new_interleaved_result (list) – list of RB results of the interleaved circuits.

• rerun_fit (bool) – re-calculate the means and fit the result.

Additional information:

Assumes that the executed ‘result’ is the output of circuits generated by randomized_benchmarking_seq.

calc_data()

Retrieve probabilities of success from execution results.

Outputs results into an internal variables: _raw_original_data and _raw_interleaved_data

calc_statistics()

Extract averages and std dev.

Output [ydata_original, ydata_interleaved]

property cliff_lengths

Return clifford lengths.

property fit

Return fit as a 2 element list.

fit_data()

Fit the interleaved RB results. Fit each of the patterns.

According to the paper: “Efficient measurement of quantum gate error by interleaved randomized benchmarking” (arXiv:1203.4550) - Equations (4) and (5).

Puts the results into a list of fit dictionaries: where each dictionary corresponds to a pattern and has fields:

• ‘epc_est’ - the estimated error per the interleaved Clifford.

• ‘epc_est_error’ - the estimated error derived from the params_err.

• ‘systematic_err’ - systematic error bound of epc_est.

• ‘systematic_err_L’ = epc_est - systematic_err (left error bound).

• ‘systematic_err_R’ = epc_est + systematic_err (right error bound).

fit_data_pattern(patt_ind, fit_guess, fit_index=0)

Fit the RB results of a particular pattern to an exponential curve.

Parameters

• patt_ind (int) – index of the data to fit.

• fit_guess (list) – guess values for the fit.

• fit_index (int) – 0 fit the standard data, 1 fit the interleaved data.

property fit_int

Return interleaved fit parameters.

plot_rb_data(pattern_index=0, ax=None, add_label=True, show_plt=True)

Plot interleaved randomized benchmarking data of a single pattern.

Parameters

• pattern_index (int) – which RB pattern to plot.

• ax (Axes) – plot axis (if passed in).

• add_label (bool) – Add an EPC label.

• show_plt (bool) – display the plot.

Raises

ImportError – if matplotlib is not installed.

property raw_data

Return raw_data as a 2 element list.

property rb_fit_fun

Return the fit function rb_fit_fun.

property rbfit_int

Return the interleaved RB fitter.

property rbfit_std

Return the original RB fitter.

property results

Return all the results as a 2 element list.

property seeds

Return the number of loaded seeds as a 2 element list.

property ydata

Return ydata (means and std devs) as a 2 element list.