0.29.1
Languages
English
Japanese
German
Korean
Portuguese, Brazilian
French
Tamil
Previous Releases
0.19
0.24
0.25
0.26
0.27
0.28
0.29
Table of Contents
Shortcuts

qiskit.algorithms.VQE.construct_expectation

VQE.construct_expectation(parameter, operator, return_expectation=False)[source]

Generate the ansatz circuit and expectation value measurement, and return their runnable composition.

Parameters

  • parameter (Union[List[float], List[Parameter], ndarray]) – Parameters for the ansatz circuit.

  • operator (OperatorBase) – Qubit operator of the Observable

  • return_expectation (bool) – If True, return the ExpectationBase expectation converter used in the construction of the expectation value. Useful e.g. to compute the standard deviation of the expectation value.

Return type

Union[OperatorBase, Tuple[OperatorBase, ExpectationBase]]

Returns

The Operator equalling the measurement of the ansatz StateFn by the Observable’s expectation StateFn, and, optionally, the expectation converter.

Raises

  • AlgorithmError – If no operator has been provided.

  • AlgorithmError – If no expectation is passed and None could be inferred via the ExpectationFactory.