# Operator Estimation¶

## Data structures¶

 ExperimentSetting(in_operator, out_operator) Input and output settings for a tomography-like experiment. TomographyExperiment(settings, program, qubits) A tomography-like experiment. ExperimentResult(setting, expectation, …) An expectation and standard deviation for the measurement of one experiment setting in a tomographic experiment.

## Methods¶

 group_experiments(experiments) Group experiments that are diagonal in a shared tensor product basis (TPB) to minimize number of QPU runs. measure_observables(qc, tomo_experiment[, …]) Measure all the observables in an TomographyExperiment.

## Utilities¶

 to_json(fn, obj) Convenience method to save pyquil.operator_estimation objects as a JSON file. read_json(fn) Convenience method to read pyquil.operator_estimation objects from a JSON file.