Skip to main contentIBM Quantum Documentation
This page is from an old version of Qiskit SDK. Go to the latest version

BaseEstimator

class BaseEstimator(circuits: Iterable[QuantumCircuit] | QuantumCircuit | None = None, observables: Iterable[SparsePauliOp] | SparsePauliOp | None = None, parameters: Iterable[Iterable[Parameter]] | None = None, **kwargs)

GitHub

Bases: qiskit.primitives.base.base_primitive.BasePrimitive

Estimator base class.

Base class for Estimator that estimates expectation values of quantum circuits and observables.

Creating an instance of an Estimator, or using one in a with context opens a session that holds resources until the instance is close() ed or the context is exited.

Parameters

  • circuits – Quantum circuits that represent quantum states.
  • observables – Observables.
  • parameters – Parameters of quantum circuits, specifying the order in which values will be bound. Defaults to [circ.parameters for circ in circuits] The indexing is such that parameters[i, j] is the j-th formal parameter of circuits[i].
  • options – Default options.

Raises

ValueError – For mismatch of circuits and parameters list.


Methods

close

BaseEstimator.close()

Close the session and free resources

run

BaseEstimator.run(circuits, observables, parameter_values=None, **run_options)

Run the job of the estimation of expectation value(s).

circuits, observables, and parameter_values should have the same length. The i-th element of the result is the expectation of observable

obs = observables[i]

for the state prepared by

circ = circuits[i]

with bound parameters

values = parameter_values[i].

Parameters

  • circuits – one or more circuit objects.
  • observables – one or more observable objects.
  • parameter_values – concrete parameters to be bound.
  • run_options – runtime options used for circuit execution.

Returns

The job object of EstimatorResult.

Raises

  • TypeError – Invalid argument type given.
  • ValueError – Invalid argument values given.

set_options

BaseEstimator.set_options(**fields)

Set options values for the estimator.

Parameters

**fields – The fields to update the options


Attributes

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.

Return type

Options

Returns

options

parameters

Parameters of the quantum circuits.

Returns

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

Was this page helpful?
Report a bug or request content on GitHub.