qiskit.algorithms.HamiltonianPhaseEstimationResult¶

class HamiltonianPhaseEstimationResult(phase_estimation_result, phase_estimation_scale, id_coefficient)[source]¶

Store and manipulate results from running HamiltonianPhaseEstimation.

This API of this class is nearly the same as PhaseEstimatorResult, differing only in the presence of an additional keyword argument in the methods. If scaled is False, then the phases are not translated and scaled to recover the eigenvalues of the Hamiltonian. Instead phi in \([0, 1)\) is returned, as is the case when then unitary is not derived from a Hamiltonian.

This class is meant to be instantiated via HamiltonianPhaseEstimation.estimate.

Parameters

phase_estimation_result (PhaseEstimationResult) – The result object returned by PhaseEstimation.estimate.
phase_estimation_scale (PhaseEstimationScale) – object used to scale phases to obtain eigenvalues.
id_coefficient (float) – The coefficient of the identity term in the Hamiltonian. Eigenvalues are computed without this term so that the coefficient must added to give correct eigenvalues. This is done automatically when retrieving eigenvalues.

__init__(phase_estimation_result, phase_estimation_scale, id_coefficient)[source]¶

Parameters

phase_estimation_result (PhaseEstimationResult) – The result object returned by PhaseEstimation.estimate.
phase_estimation_scale (PhaseEstimationScale) – object used to scale phases to obtain eigenvalues.
id_coefficient (float) – The coefficient of the identity term in the Hamiltonian. Eigenvalues are computed without this term so that the coefficient must added to give correct eigenvalues. This is done automatically when retrieving eigenvalues.

Methods

__init__(phase_estimation_result, …)

type phase_estimation_result: PhaseEstimationResult

combine(result)

Any property from the argument that exists in the receiver is updated.

filter_phases([cutoff, scaled, as_float])

Filter phases as does PhaseEstimatorResult.filter_phases, with the addition that phi is shifted and translated to return eigenvalues of the Hamiltonian.

Attributes

`most_likely_eigenvalue`	The most likely eigenvalue of the Hamiltonian.
`most_likely_phase`	The most likely phase of the unitary corresponding to the Hamiltonian.

combine(result)¶

Any property from the argument that exists in the receiver is updated. :type result: AlgorithmResult :param result: Argument result with properties to be set.

Raises: TypeError – Argument is None
Return type: None

filter_phases(cutoff=0.0, scaled=True, as_float=True)[source]¶

Filter phases as does PhaseEstimatorResult.filter_phases, with the addition that phi is shifted and translated to return eigenvalues of the Hamiltonian.

Parameters

cutoff (float) – Minimum weight of number of counts required to keep a bit string. The default value is 0.0.
scaled (bool) – If False, return phi in \([0, 1)\) rather than the eigenvalues of the Hamiltonian.
as_float (bool) – If True, returned keys are floats in \([0.0, 1.0)\). If False returned keys are bit strings.

Raises

ValueError – if as_float is False and scaled is True.

Return type

Dict[Union[str, float], float]

Returns

A dict of filtered phases.

property most_likely_eigenvalue¶

The most likely eigenvalue of the Hamiltonian.

This method calls most_likely_phase and scales the result to obtain an eigenvalue.

Return type: float
Returns: The most likely eigenvalue of the Hamiltonian.

property most_likely_phase¶

The most likely phase of the unitary corresponding to the Hamiltonian.

Return type: float
Returns: The most likely phase.