qiskit.optimization.algorithms.MultiStartOptimizer¶

class MultiStartOptimizer(trials=1, clip=100.0)[source]¶

An abstract class that implements multi start optimization and should be sub-classed by other optimizers.

Constructs an instance of this optimizer.

Parameters

trials (int) – The number of trials for multi-start method. The first trial is solved with the initial guess of zero. If more than one trial is specified then initial guesses are uniformly drawn from [lowerbound, upperbound] with potential clipping.
clip (float) – Clipping parameter for the initial guesses in the multi-start method. If a variable is unbounded then the lower bound and/or upper bound are replaced with the -clip or clip values correspondingly for the initial guesses.

__init__(trials=1, clip=100.0)[source]¶

Constructs an instance of this optimizer.

Parameters

trials (int) – The number of trials for multi-start method. The first trial is solved with the initial guess of zero. If more than one trial is specified then initial guesses are uniformly drawn from [lowerbound, upperbound] with potential clipping.
clip (float) – Clipping parameter for the initial guesses in the multi-start method. If a variable is unbounded then the lower bound and/or upper bound are replaced with the -clip or clip values correspondingly for the initial guesses.

Methods

`__init__`([trials, clip])	Constructs an instance of this optimizer.
`get_compatibility_msg`(problem)	Checks whether a given problem can be solved with the optimizer implementing this method.
`is_compatible`(problem)	Checks whether a given problem can be solved with the optimizer implementing this method.
`multi_start_solve`(minimize, problem)	Applies a multi start method given a local optimizer.
`solve`(problem)	Tries to solves the given problem using the optimizer.

Attributes

`clip`	Returns the clip value for this optimizer.
`trials`	Returns the number of trials for this optimizer.

property clip¶

Returns the clip value for this optimizer.

abstract get_compatibility_msg(problem)¶

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

Parameters: problem (QuadraticProgram) – The optimization problem to check compatibility.
Return type: str
Returns: Returns the incompatibility message. If the message is empty no issues were found.

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.
Return type: bool
Returns: Returns True if the problem is compatible, False otherwise.

multi_start_solve(minimize, problem)[source]¶

Applies a multi start method given a local optimizer.

Parameters

minimize (Callable[[array], Tuple[array, Any]]) – A callable object that minimizes the problem specified
problem (QuadraticProgram) – A problem to solve

Return type

OptimizationResult

Returns

The result of the multi start algorithm applied to the problem.

abstract solve(problem)¶

Tries to solves the given problem using the optimizer.

Runs the optimizer to try to solve the optimization problem.

Parameters: problem (QuadraticProgram) – The problem to be solved.
Return type: OptimizationResult
Returns: The result of the optimizer applied to the problem.
Raises: QiskitOptimizationError – If the problem is incompatible with the optimizer.

property trials¶

Returns the number of trials for this optimizer.