qiskit.chemistry.algorithms.GroundStateEigensolver¶

class GroundStateEigensolver(transformation, solver)[source]¶

Ground state computation using a minimum eigensolver.

Parameters

transformation (Transformation) – Qubit Operator Transformation
solver (Union[MinimumEigensolver, MinimumEigensolverFactory]) – Minimum Eigensolver or MESFactory object, e.g. the VQEUCCSDFactory.

__init__(transformation, solver)[source]¶

Parameters

transformation (Transformation) – Qubit Operator Transformation
solver (Union[MinimumEigensolver, MinimumEigensolverFactory]) – Minimum Eigensolver or MESFactory object, e.g. the VQEUCCSDFactory.

Methods

`__init__`(transformation, solver)	type transformation `Transformation`
`evaluate_operators`(state, operators)	Evaluates additional operators at the given state.
`returns_groundstate`()	Whether the eigensolver returns the ground state or only ground state energy.
`solve`(driver[, aux_operators])	Compute Ground State properties.

Attributes

`solver`	Returns the minimum eigensolver or factory.
`transformation`	Returns the transformation used to obtain a qubit operator from the molecule.

evaluate_operators(state, operators)[source]¶

Evaluates additional operators at the given state.

Parameters

state (Union[str, dict, Result, list, ndarray, Statevector, QuantumCircuit, Instruction, OperatorBase]) – any kind of input that can be used to specify a state. See also StateFn for more details.
operators (Union[WeightedPauliOperator, OperatorBase, list, dict]) – either a single, list or dictionary of WeightedPauliOperator``s or any kind of operator implementing the ``OperatorBase.

Return type

Union[float, List[float], Dict[str, List[float]]]

Returns

The expectation value of the given operator(s). The return type will be identical to the format of the provided operators.

returns_groundstate()[source]¶

Whether the eigensolver returns the ground state or only ground state energy.

solve(driver, aux_operators=None)[source]¶

Compute Ground State properties.

Parameters

driver (BaseDriver) – a chemistry driver object which defines the chemical problem that is to be solved by this calculation.
aux_operators (Union[List[FermionicOperator], List[BosonicOperator], None]) – Additional auxiliary operators to evaluate at the ground state. Depending on whether a fermionic or bosonic system is solved, the type of the operators must be FermionicOperator or BosonicOperator, respectively.

Raises

NotImplementedError – If an operator in aux_operators is not of type FermionicOperator.

Return type

Union[ElectronicStructureResult, VibronicStructureResult]

Returns

An eigenstate result. Depending on the transformation this can be an electronic structure or bosonic result.

property solver¶

Returns the minimum eigensolver or factory.

property transformation¶

Returns the transformation used to obtain a qubit operator from the molecule.