# C贸digo fuente para qiskit.algorithms.minimum_eigensolvers.minimum_eigensolver

```# This code is part of Qiskit.
#
#
# obtain a copy of this license in the LICENSE.txt file in the root directory
#
# Any modifications or derivative works of this code must retain this
# copyright notice, and modified files need to carry a notice indicating
# that they have been altered from the originals.

"""The minimum eigensolver interface and result."""

from __future__ import annotations

from abc import ABC, abstractmethod
from typing import Any

from qiskit.opflow import PauliSumOp
from qiskit.quantum_info.operators.base_operator import BaseOperator

from ..algorithm_result import AlgorithmResult
from ..list_or_dict import ListOrDict

[documentos]class MinimumEigensolver(ABC):
"""The minimum eigensolver interface.

Algorithms that can compute a minimum eigenvalue for an operator may implement this interface to
allow different algorithms to be used interchangeably.
"""

[documentos]    @abstractmethod
def compute_minimum_eigenvalue(
self,
operator: BaseOperator | PauliSumOp,
aux_operators: ListOrDict[BaseOperator | PauliSumOp] | None = None,
) -> "MinimumEigensolverResult":
"""
Computes the minimum eigenvalue. The ``operator`` and ``aux_operators`` are supplied here.
While an ``operator`` is required by algorithms, ``aux_operators`` are optional.

Args:
operator: Qubit operator of the observable.
aux_operators: Optional list of auxiliary operators to be evaluated with the
parameters of the minimum eigenvalue main result and their expectation values
returned. For instance in chemistry these can be dipole operators and total particle
count operators, so we can get values for these at the ground state.

Returns:
A minimum eigensolver result.
"""
return MinimumEigensolverResult()

[documentos]    @classmethod
def supports_aux_operators(cls) -> bool:
"""Whether computing the expectation value of auxiliary operators is supported.

If the minimum eigensolver computes an eigenvalue of the main ``operator`` then it can
compute the expectation value of the ``aux_operators`` for that state. Otherwise they will
be ignored.

Returns:
True if aux_operator expectations can be evaluated, False otherwise
"""
return False

[documentos]class MinimumEigensolverResult(AlgorithmResult):
"""Minimum eigensolver result."""

def __init__(self) -> None:
super().__init__()
self._eigenvalue: complex | None = None
self._aux_operators_evaluated: ListOrDict[tuple[complex, dict[str, Any]]] | None = None

@property
def eigenvalue(self) -> complex | None:
"""The computed minimum eigenvalue."""
return self._eigenvalue

@eigenvalue.setter
def eigenvalue(self, value: complex) -> None:
self._eigenvalue = value

@property
def aux_operators_evaluated(self) -> ListOrDict[tuple[complex, dict[str, Any]]] | None:
"""The aux operator expectation values.

These values are in fact tuples formatted as (mean, (variance, shots)).
"""
return self._aux_operators_evaluated

@aux_operators_evaluated.setter
def aux_operators_evaluated(self, value: ListOrDict[tuple[complex, dict[str, Any]]]) -> None:
self._aux_operators_evaluated = value
```