localsolver.LSPhase Class Reference

Detailed Description

Optimization phase.

Since LocalSolver allows lexicographic multiobjective optimization, we allow you to parameterize the time or the number of iterations to spend in optimizing each objective. When multiple objectives are declared, these objectives are optimized in lexicographic order (in the order of their declaration in the model). Thus, if k objectives 0, ..., k-1 are declared, each objective i can be optimized while maintaining the values of objectives 0, ..., i-1 previously obtained and ignoring the values of objectives i+1, ..., k-1. During such an optimization phase, objective i is called the optimized objective. At least one phase must be created to launch the solver. If you have only one objective to optimize, then create a phase, set the time or the number of iterations, and run the solver. By default, the optimized objective of a phase corresponds to the last objective declared in the model (in this case, all objectives of the model are optimized together).

Public Member Functions
LocalSolver	GetLocalSolver ()
	Returns the LocalSolver object associated to this phase.
void	SetTimeLimit (int timeLimit)
	Sets the time limit of this phase in seconds.
int	GetTimeLimit ()
	Gets the time limit of this phase in seconds.
void	SetIterationLimit (long iterationLimit)
	Sets the number of iterations of this phase.
long	GetIterationLimit ()
	Gets the number of iterations of this phase.
void	SetOptimizedObjective (int objectiveIndex)
	Sets the optimized objective of this phase.
int	GetOptimizedObjective ()
	Gets the index of the optimized objective.
void	SetEnabled (bool enabled)
	Sets the enabled status of this phase.
bool	IsEnabled ()
	Returns true if the phase is enabled, False otherwise.
LSStatistics	GetStatistics ()
	Gets the statistics of this phase.
override string	ToString ()
	Returns a string representation of this phase.

Member Function Documentation

LocalSolver localsolver.LSPhase.GetLocalSolver

(

)

Returns the LocalSolver object associated to this phase.

Returns

LocalSolver object

void localsolver.LSPhase.SetTimeLimit

(

int

timeLimit

)

Sets the time limit of this phase in seconds.

Note that the "real" time (that is, total time) spent to resolve the model is considered here (and not only the CPU time). The default time limit is set to the largest positive integer on 32 bits, that is 2^31-1 = 2,147,483,647 > 10^9. Only allowed in state LSState::Stopped.

Parameters

timeLimit

Time limit in seconds.

int localsolver.LSPhase.GetTimeLimit

(

)

Gets the time limit of this phase in seconds.

Only allowed in states LSState::Paused or LSState::Stopped.

Returns

Time limit in seconds.

See Also

LSPhase.SetTimeLimit

void localsolver.LSPhase.SetIterationLimit

(

long

iterationLimit

)

Sets the number of iterations of this phase.

Fixing the seed and the number of iterations of all phases ensures the reproducibility of results over several runs. The default number of iterations is set to the largest positive integer on 64 bits, that is 2^63-1 = 9,223,372,036,854,775,807 > 10^18. Only allowed in state LSState::Stopped.

Parameters

iterationLimit

Iteration limit.

long localsolver.LSPhase.GetIterationLimit

(

)

Gets the number of iterations of this phase.

Only allowed in states LSState::Paused or LSState::Stopped.

Returns

Iteration limit.

See Also

LSPhase.SetIterationLimit

void localsolver.LSPhase.SetOptimizedObjective

(

int

objectiveIndex

)

Sets the optimized objective of this phase.

When multiple objectives are declared, these objectives are optimized in lexicographic order (in the order of their declaration in the model). Thus, if k objectives 0, ..., k-1 are declared, each objective i can be optimized while maintaining the values of objectives 0, ..., i-1 previously obtained and ignoring the values of objectives i+1, ..., k-1. By default, the optimized objective corresponds to the last objective declared in the model. Only allowed in state LSState::Stopped.

Parameters

objectiveIndex

Index of the optimized objective.

int localsolver.LSPhase.GetOptimizedObjective

(

)

Gets the index of the optimized objective.

Only allowed in states LSState::Paused or LSState::Stopped.

Returns

Index of the optimized objective.

See Also

LSPhase.SetOptimizedObjective

void localsolver.LSPhase.SetEnabled

(

bool

enabled

)

Sets the enabled status of this phase.

The solver only optimize enabled phases. Disabling a phase can be useful when an objective has been removed from the model by LSModel::RemoveObjective. By default, a phase is enabled. Only allowed in state LSState::Stopped.

Parameters

enabled

True to enable the phase, False to disable it

Since version 5.0

bool localsolver.LSPhase.IsEnabled

(

)

Returns true if the phase is enabled, False otherwise.

Only allowed in states LSState::Paused or LSState::Stopped.

Returns

True if phase is enabled

Since version 5.0

LSStatistics localsolver.LSPhase.GetStatistics

(

)

Gets the statistics of this phase.

Statistics are reset to zero before each resolution. Only allowed in states LSState::Paused or LSState::Stopped. Note that for performance reasons, this function always returns the same object.

Returns

Statistics.

See Also

LSStatistics

override string localsolver.LSPhase.ToString

(

)

Returns a string representation of this phase.

Useful for debugging or logging purposes.

Returns

String representation.