GroverOptimizer

class GroverOptimizer(num_value_qubits, num_iterations=3, converters=None, penalty=None, sampler=None, pass_manager=None)[source]

Bases: OptimizationAlgorithm

Uses Grover Adaptive Search (GAS) to find the minimum of a QUBO function.

Parameters:

  • num_value_qubits (int) – The number of value qubits.

  • num_iterations (int) – The number of iterations the algorithm will search with no improvement.

  • converters (QuadraticProgramConverter | list[QuadraticProgramConverter] | None) – The converters to use for converting a problem into a different form. By default, when None is specified, an internally created instance of QuadraticProgramToQubo will be used.

  • penalty (float | None) – The penalty factor used in the default QuadraticProgramToQubo converter

  • sampler (BaseSamplerV1 | BaseSamplerV2 | None) – A Sampler to use for sampling the results of the circuits.

  • pass_manager (BasePassManager | None) – A pass manager to use to transpile the circuits

Raises:

  • ValueError – If both a quantum instance and sampler are set.

  • TypeError – When there one of converters is an invalid type.

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

solve(problem)[source]

Tries to solve the given problem using the grover optimizer.

Runs the optimizer to try to solve the optimization problem. If the problem cannot be, converted to a QUBO, this optimizer raises an exception due to incompatibility.

Parameters:

problem (QuadraticProgram) – The problem to be solved.

Returns:

The result of the optimizer applied to the problem.

Raises:
Return type:

OptimizationResult