qiskit.algorithms.VQE.get_energy_evaluation

VQE.get_energy_evaluation(operator, return_expectation=False)

Returns a function handle to evaluates the energy at given parameters for the ansatz.

This is the objective function to be passed to the optimizer that is used for evaluation.

Paramètres

• operator (OperatorBase) – The operator whose energy to evaluate.

• return_expectation (bool) – If True, return the ExpectationBase expectation converter used in the construction of the expectation value. Useful e.g. to evaluate other operators with the same expectation value converter.

Renvoie

Energy of the hamiltonian of each parameter, and, optionally, the expectation converter.

Lève

RuntimeError – If the circuit is not parameterized (i.e. has 0 free parameters).

Type renvoyé

Callable[[np.ndarray], float | list[float]] | tuple[Callable[[np.ndarray], float | list[float]], ExpectationBase]