QuantumRandomAccessOptimizer#

class QuantumRandomAccessOptimizer(min_eigen_solver, max_vars_per_qubit=3, rounding_scheme=None, *, penalty=None)[source]#

Bases: OptimizationAlgorithm

Quantum Random Access Optimizer class.

Parameters:

min_eigen_solver (MinimumEigensolver) – The minimum eigensolver to use for solving the relaxed problem.
max_vars_per_qubit (int) – The maximum number of decision variables per qubit. Integer values 1, 2 and 3 are supported (default to 3).
rounding_scheme (RoundingScheme | None) – The rounding scheme. If None is provided, SemideterministicRounding will be used.
penalty (float | None) – The penalty factor to use for the QuadraticProgramToQubo converter.

Raises:

ValueError – If the maximum number of variables per qubit is not 1, 2, or 3.
TypeError – If the provided minimum eigensolver does not support auxiliary operators.

Attributes

max_vars_per_qubit#: Return the maximum number of variables per qubit.

min_eigen_solver#: Return the minimum eigensolver.

rounding_scheme#: Return the rounding scheme.

Methods

get_compatibility_msg(problem)[source]#

Checks whether a given problem can be solved with this optimizer.

Checks whether the given problem is compatible, i.e., whether the problem can be converted to a QUBO, and otherwise, returns a message explaining the incompatibility.

Parameters:: problem (QuadraticProgram) – The optimization problem to check compatibility.
Returns:: A message describing the incompatibility.
Return type:: str

is_compatible(problem)#

Checks whether a given problem can be solved with the optimizer implementing this method.

Parameters:: problem (QuadraticProgram) – The optimization problem to check compatibility.
Returns:: Returns True if the problem is compatible, False otherwise.
Return type:: bool

process_result(problem, encoding, relaxed_result, rounding_result)[source]#

Process the relaxed result of the minimum eigensolver and rounding scheme.

Parameters:

problem (QuadraticProgram) – The QuadraticProgram to be solved.
encoding (QuantumRandomAccessEncoding) – An encoding instance for which encode() has already been called so it has been encoded with a QuadraticProgram.
relaxed_result (MinimumEigensolverResult) – The relaxed result of the minimum eigensolver.
rounding_result (RoundingResult) – The result of the rounding scheme.

Returns:

The result of the quantum random access optimization.

Return type:

QuantumRandomAccessOptimizationResult

solve(problem)[source]#

Solve the relaxed Hamiltonian given by the encoding and round the solution by the given rounding scheme.

Parameters:: problem (QuadraticProgram) – The QuadraticProgram to be solved.
Returns:: The result of the quantum random access optimization.
Raises:: ValueError – If the encoding has not been encoded with a QuadraticProgram.
Return type:: QuantumRandomAccessOptimizationResult

solve_relaxed(encoding)[source]#

Solve the relaxed Hamiltonian given by the encoding.

Note

This method uses the encoding instance given as encoding and ignores max_vars_per_qubit().

Parameters:: encoding (QuantumRandomAccessEncoding) – An encoding instance for which encode() has already been called so it has been encoded with a QuadraticProgram.
Returns:: The result of the minimum eigensolver, and the rounding context.
Raises:: ValueError – If the encoding has not been encoded with a QuadraticProgram.
Return type:: tuple[MinimumEigensolverResult, RoundingContext]