qiskit.optimization.algorithms.MultiStartOptimizer
class MultiStartOptimizer(trials=1, clip=100.0)
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-cliporclipvalues correspondingly for the initial guesses.
__init__
__init__(trials=1, clip=100.0)
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-cliporclipvalues 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. |
clip
Returns the clip value for this optimizer.
Return type
float
Returns
The clip value.
get_compatibility_msg
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
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
multi_start_solve(minimize, problem)
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.
solve
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.
trials
Returns the number of trials for this optimizer.
Return type
int
Returns
The number of trials.