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LSParam Class

class LSParam

Solving parameters. This class contains some methods allowing you to parameterize the resolution of the model. For the sake of simplicity, only a few parameters are actually offered to tune the search.

Summary

Functions

setSeed

Sets the seed of the pseudo-random number generator used by the solver.

getSeed

Gets the seed of the pseudo-random number generator used by the solver.

setNbThreads

Sets the number of threads used to parallelize the search.

getNbThreads

Gets the number of threads requested by the user.

setTimeLimit

Sets the time limit in seconds.

getTimeLimit

Gets the time limit in seconds.

setIterationLimit

Sets the maximum number of iterations.

getIterationLimit

Gets the maximum number of iterations.

setAnnealingLevel

Deprecated since version 8.5: This parameter does not have a significant influence on the search anymore.

getAnnealingLevel

Deprecated since version 8.5: This parameter does not have a significant influence on the search anymore.

setVerbosity

Sets the verbosity level of the solver.

getVerbosity

Gets the verbosity level of the solver.

setObjectiveThreshold

Sets the threshold of the objective with the given index.

setObjectiveThreshold

Sets the threshold of the objective with the given index.

setIntObjectiveThreshold

Sets the threshold of the objective with the given index.

setDoubleObjectiveThreshold

Sets the threshold of the objective with the given index.

getObjectiveThreshold

Gets the threshold of the objective with the given index.

getIntObjectiveThreshold

Gets the threshold of the objective with the given index.

getDoubleObjectiveThreshold

Gets the threshold of the objective with the given index.

setTimeBetweenDisplays

Sets the time in seconds between two consecutive displays in console while the solver is running.

getTimeBetweenDisplays

Gets the time in seconds between two consecutive displays in console while the solver is running.

setTimeBetweenTicks

Sets the time in seconds between two events of type CT_TimeTicked.

getTimeBetweenTicks

Gets the time in seconds between two events of type CT_TimeTicked.

setIterationBetweenTicks

Sets the number of iterations between two events of type CT_IterationTicked.

getIterationBetweenTicks

Gets the number of iterations between two events of type CT_IterationTicked.

setLogWriter

Sets the writer used by LocalSolver for its logging.

getLogWriter

Returns the writer used by LocalSolver for its logging.

setLogFile

Sets the path of the LocalSolver log file.

getLogFile

Returns the path of the LocalSolver log file.

setAdvancedParam

Sets the value of an advanced parameter.

setAdvancedParam

Sets the value of an advanced parameter.

setAdvancedParam

Sets the value of an advanced parameter.

getAdvancedParam

Returns the value of an advanced parameter.

getAdvancedParam

Returns the value of an advanced parameter.

getAdvancedParam

Returns the value of an advanced parameter.

getAdvancedParam

Returns the value of an advanced parameter.

toString

Returns a string representation of these parameters.

Functions

void LSParam::setSeed(int seed)

Sets the seed of the pseudo-random number generator used by the solver. The seed must be a positive integer. The default seed is set to 0. Only allowed in states S_Modeling or S_Stopped.

The search for solutions is highly randomized. Fixing the seed and the number of iterations of the solver allows you to reproduce exactly its results over several runs.

Parameters

seed – Seed of the pseudo-random number generator.

int LSParam::getSeed() const

Gets the seed of the pseudo-random number generator used by the solver.

Returns

Seed of the pseudo-random number generator.

See

LSParam::setSeed()

void LSParam::setNbThreads(int nbThreads)

Sets the number of threads used to parallelize the search. The number of threads must be a positive integer. The default number of threads is set to 0 which means that the number of threads is automatically adapted to your computer and to your optimization model. Only allowed in states S_Modeling or S_Stopped. This parameter is indicative, if needed LocalSolver may use more threads. The actual number of threads can also vary during the search.

Parameters

nbThreads – Number of threads.

int LSParam::getNbThreads() const

Gets the number of threads requested by the user.

Returns

Number of threads (by convention, 0 means that the number of threads is automatically adapted to your computer and to your optimization model).

See

LSParam::setNbThreads()

void LSParam::setTimeLimit(int timeLimit)

Sets the time limit in seconds. Only allowed in states S_Modeling or S_Stopped.

Parameters

timeLimit – Time limit in seconds.

See

LSPhase

int LSParam::getTimeLimit()

Gets the time limit in seconds.

Returns

Time limit in seconds.

See

LSParam::setTimeLimit()

See

LSPhase

void LSParam::setIterationLimit(long long iterationLimit)

Sets the maximum number of iterations. Fixing the seed and the number of iterations ensures the reproducibility of results over several runs. Only allowed in states S_Modeling or S_Stopped.

Parameters

iterationLimit – Iteration limit.

See

LSPhase

long long LSParam::getIterationLimit()

Gets the maximum number of iterations.

Returns

Iteration limit.

See

LSParam::setIterationLimit()

See

LSPhase

void LSParam::setAnnealingLevel(int annealingLevel)

Deprecated since version 8.5: This parameter does not have a significant influence on the search anymore. The tuning of this parameter won’t be allowed in a future version.

Sets the simulated annealing level. The level must be an integer between 0 and 9. The default simulated annealing level is set to 1. Only allowed in states S_Modeling or S_Stopped.

Parameters

annealingLevel – Simulated annealing level.

int LSParam::getAnnealingLevel() const

Deprecated since version 8.5: This parameter does not have a significant influence on the search anymore. The tuning of this parameter won’t be allowed in a future version.

Gets the simulated annealing level.

Returns

Simulated annealing level.

See

LSParam::setAnnealingLevel()

void LSParam::setVerbosity(int verbosity)

Sets the verbosity level of the solver. The default verbosity is set to 1. Only allowed in states S_Modeling or S_Stopped. There are 3 defined verbosity levels:

  • 0: All the traces are disabled.

  • 1: Normal verbosity. This is the default level.

  • 2: Detailed verbosity. Displays statistics during the search.

Parameters

verbosity – Verbosity level: 0, 1, 2.

int LSParam::getVerbosity() const

Gets the verbosity level of the solver.

Returns

verbosity Verbosity level: 0, 1 or 2.

See

LSParam::setVerbosity()

void LSParam::setObjectiveThreshold(int objectiveIndex, lsint threshold)

Sets the threshold of the objective with the given index. If the objective is minimized (resp. maximized), then the optimization of this objective is stopped as soon as this lower (resp. upper) threshold is reached. It can be useful for goal programming. Only allowed in state S_Stopped. This method has the same behavior as LSParam::setIntObjectiveThreshold().

Parameters
  • objectiveIndex – Index of the objective.

  • threshold – Objective threshold.

See

LSExpression::isObjective()

See

LSExpression::isInt()

Since

8.5

void LSParam::setObjectiveThreshold(int objectiveIndex, lsdouble threshold)

Sets the threshold of the objective with the given index. If the objective is minimized (resp. maximized), then the optimization of this objective is stopped as soon as this lower (resp. upper) threshold is reached. It can be useful for goal programming. Only allowed in state S_Stopped. This method has the same behavior as LSParam::setDoubleObjectiveThreshold().

Parameters
  • objectiveIndex – Index of the objective.

  • threshold – Objective threshold.

See

LSExpression::isObjective()

See

LSExpression::isDouble()

Since

8.5

void LSParam::setIntObjectiveThreshold(int objectiveIndex, lsint threshold)

Sets the threshold of the objective with the given index. If the objective is minimized (resp. maximized), then the optimization of this objective is stopped as soon as this lower (resp. upper) threshold is reached. It can be useful for goal programming. Only allowed in state S_Stopped.

Parameters
  • objectiveIndex – Index of the objective.

  • threshold – Objective threshold.

See

LSExpression::isObjective()

See

LSExpression::isInt()

Since

8.5

void LSParam::setDoubleObjectiveThreshold(int objectiveIndex, lsdouble threshold)

Sets the threshold of the objective with the given index. If the objective is minimized (resp. maximized), then the optimization of this objective is stopped as soon as this lower (resp. upper) threshold is reached. It can be useful for goal programming. Only allowed in state S_Stopped.

Parameters
  • objectiveIndex – Index of the objective.

  • threshold – Objective threshold.

See

LSExpression::isObjective()

See

LSExpression::isDouble()

Since

8.5

lsint LSParam::getObjectiveThreshold(int objectiveIndex) const

Gets the threshold of the objective with the given index. Only allowed in states S_Paused or S_Stopped.

Parameters

objectiveIndex – Index of the objective.

Returns

Objective threshold.

See

LSParam::setObjectiveThreshold() lsint)

Since

8.5

lsint LSParam::getIntObjectiveThreshold(int objectiveIndex) const

Gets the threshold of the objective with the given index. Only allowed in states S_Paused or S_Stopped.

Parameters

objectiveIndex – Index of the objective.

Returns

Objective threshold.

See

LSParam::setIntObjectiveThreshold() lsint)

Since

8.5

lsdouble LSParam::getDoubleObjectiveThreshold(int objectiveIndex) const

Gets the threshold of the objective with the given index. Only allowed in states S_Paused or S_Stopped.

Parameters

objectiveIndex – Index of the objective.

Returns

Objective threshold.

See

LSParam::setObjectiveThreshold() lsint)

Since

3.0

void LSParam::setTimeBetweenDisplays(int timeBetweenDisplays)

Sets the time in seconds between two consecutive displays in console while the solver is running. The default time between displays is set to 1 second. Only allowed in states S_Modeling or S_Stopped.

Parameters

timeBetweenDisplays – Time in seconds between displays.

int LSParam::getTimeBetweenDisplays() const

Gets the time in seconds between two consecutive displays in console while the solver is running.

Returns

Time in seconds between displays.

See

LSParam::setTimeBetweenDisplays()

void LSParam::setTimeBetweenTicks(int timeBetweenTicks)

Sets the time in seconds between two events of type CT_TimeTicked. The default time between ticks is set to 1 second. Only allowed in states S_Modeling or S_Stopped.

Parameters

timeBetweenTicks – Time in seconds between ticks.

Since

6.0

int LSParam::getTimeBetweenTicks() const

Gets the time in seconds between two events of type CT_TimeTicked.

Returns

Time in seconds between ticks.

See

LSParam::setTimeBetweenTicks()

Since

6.0

void LSParam::setIterationBetweenTicks(long long iterationBetweenTicks)

Sets the number of iterations between two events of type CT_IterationTicked. The default number of iterations between ticks is set to 10,000. Only allowed in states S_Modeling or S_Stopped.

Parameters

iterationBetweenTicks – Number of iterations between ticks.

Since

6.0

long long LSParam::getIterationBetweenTicks() const

Gets the number of iterations between two events of type CT_IterationTicked.

Returns

Number of iterations between ticks.

See

LSParam::setIterationBetweenTicks()

Since

6.0

void LSParam::setLogWriter(std::streambuf *writer)

Sets the writer used by LocalSolver for its logging. The default is to log to the standard output. To tune the logging verbosity of the output or to disable logging, see LSParam::setVerbosity(). Note that you can specify both the log writer and the log file by using the method LSParam::setLogFile().

Parameters

writer – Writer to use for the logging or null to restore the default writer.

Since

9.5

std::streambuf *LSParam::getLogWriter() const

Returns the writer used by LocalSolver for its logging. The default value is null and means “logging to the standard output”. To tune the logging verbosity of the output or to disable logging, see LSParam::setVerbosity().

Returns

The writer used by LocalSolver for its logging.

See

LSParam::setLogWriter().

Since

9.5

void LSParam::setLogFile(const std::string &path)

Sets the path of the LocalSolver log file. If the path is empty, no log wil be saved. To tune the logging verbosity, see LSParam::setVerbosity(). Only allowed in states S_Modeling or S_Stopped.

Parameters

path – Path of the log file. Leave empty to disable the logging mechanism.

See

LSParam::setVerbosity()

See

LSParam::getLogFile()

std::string LSParam::getLogFile() const

Returns the path of the LocalSolver log file. If no log file was specified, an empty string is returned.

Returns

The path of the log file or an empty string.

See

LSParam::setLogFile()

void LSParam::setAdvancedParam(const std::string &key, int value)

Sets the value of an advanced parameter. Advanced parameters are reserved for fine tuning or debugging and should not be used by end-users. Only allowed in states S_Modeling or S_Stopped.

Parameters
  • key – Name of the parameter.

  • value – Value of the parameter.

void LSParam::setAdvancedParam(const std::string &key, double value)

Sets the value of an advanced parameter. Advanced parameters are reserved for fine tuning or debugging and should not be used by end-users. Only allowed in states S_Modeling or S_Stopped.

Parameters
  • key – Name of the parameter.

  • value – Value of the parameter.

void LSParam::setAdvancedParam(const std::string &key, const std::string &value)

Sets the value of an advanced parameter. Advanced parameters are reserved for fine tuning or debugging and should not be used by end-users. Only allowed in states S_Modeling or S_Stopped.

Parameters
  • key – Name of the parameter.

  • value – Value of the parameter.

int LSParam::getAdvancedParam(const std::string &key) const

Returns the value of an advanced parameter. Advanced parameters are reserved for fine tuning or debugging and should not be used by end-users. Throws an exception if the parameter does not exist.

Parameters

key – Name of the parameter.

Returns

Value of the parameter.

See

LSParam::setAdvancedParam()

int LSParam::getAdvancedParam(const std::string &key, int defaultValue) const

Returns the value of an advanced parameter. Advanced parameters are reserved for fine tuning or debugging and should not be used by end-users. The default value is returned if the parameter does not exist or if no value is defined for this parameter.

Parameters
  • key – Name of the parameter.

  • defaultValue – Default value.

See

LSParam::setAdvancedParam()

double LSParam::getAdvancedParam(const std::string &key, double defaultValue) const

Returns the value of an advanced parameter. Advanced parameters are reserved for fine tuning or debugging and should not be used by end-users. The default value is returned if the parameter does not exist or if no value is defined for this parameter.

Parameters
  • key – Name of the parameter.

  • defaultValue – Default value.

See

LSParam::setAdvancedParam()

std::string LSParam::getAdvancedParam(const std::string &key, const std::string &defaultValue) const

Returns the value of an advanced parameter. Advanced parameters are reserved for fine tuning or debugging and should not be used by end-users. The default value is returned if the parameter does not exist or if no value is defined for this parameter.

Parameters
  • key – Name of the parameter.

  • defaultValue – Default value of the parameter.

See

LSParam::setAdvancedParam()

std::string LSParam::toString() const

Returns a string representation of these parameters. Useful for debugging or logging purposes.

Returns

String representation.