BackendEstimator

class BackendEstimator(backend, options=None, abelian_grouping=True, bound_pass_manager=None, skip_transpilation=False)

Bases: BaseEstimator[PrimitiveJob[EstimatorResult]]

Evaluates expectation value using Pauli rotation gates.

The BackendEstimator class is a generic implementation of the BaseEstimator interface that is used to wrap a BackendV2 (or BackendV1) object in the BaseEstimator API. It facilitates using backends that do not provide a native BaseEstimator implementation in places that work with BaseEstimator, such as algorithms in qiskit.algorithms including VQE. However, if you're using a provider that has a native implementation of BaseEstimator, it is a better choice to leverage that native implementation as it will likely include additional optimizations and be a more efficient implementation. The generic nature of this class precludes doing any provider- or backend-specific optimizations.

Initalize a new BackendEstimator instance

Parameters

• backend -- Required: the backend to run the primitive on

• options -- Default options.

• abelian_grouping -- Whether the observable should be grouped into commuting

• bound_pass_manager -- An optional pass manager to run after parameter binding.

• skip_transpilation -- If this is set to True the internal compilation of the input circuits is skipped and the circuit objects will be directly executed when this object is called.

Methods

run	Run the job of the estimation of expectation value(s).
set_options	Set options values for the estimator.
set_transpile_options	Set the transpiler options for transpiler.

Attributes

backend

Returns: The backend which this estimator object based on

circuits

Quantum circuits that represents quantum states.

Returns

The quantum circuits.

observables

Observables to be estimated.

Returns

The observables.

options

Return options values for the estimator.

Returns

options

parameters

Parameters of the quantum circuits.

Returns

Parameters, where parameters[i][j] is the j-th parameter of the i-th circuit.

preprocessed_circuits

Transpiled quantum circuits produced by preprocessing :returns: List of the transpiled quantum circuit

transpile_options

Return the transpiler options for transpiling the circuits.

transpiled_circuits

Transpiled quantum circuits. :returns: List of the transpiled quantum circuit

Raises

QiskitError -- if the instance has been closed.