Detailed Description

This class stores parameter settings for LP and MIP solvers.

Some parameters are marked as advanced: do not change their values unless you know what you are doing!

For developers: how to add a new parameter:

Add the new Foo parameter in the DoubleParam or IntegerParam enum.
If it is a categorical param, add a FooValues enum.
Decide if the wrapper should define a default value for it: yes if it controls the properties of the solution (example: tolerances) or if it consistently improves performance, no otherwise. If yes, define kDefaultFoo.
Add a foo_value_ member and, if no default value is defined, a foo_is_default_ member.
Add code to handle Foo in Set...Param, Reset...Param, Get...Param, Reset and the constructor.
In class MPSolverInterface, add a virtual method SetFoo, add it to SetCommonParameters or SetMIPParameters, and implement it for each solver. Sometimes, parameters need to be implemented differently, see for example the INCREMENTALITY implementation.
Add a test in linear_solver_test.cc.

TODO(user): store the parameter values in a protocol buffer instead. We need to figure out how to deal with the subtleties of the default values.

Definition at line 1304 of file linear_solver.h.

Public Types
enum	DoubleParam { RELATIVE_MIP_GAP = 0, PRIMAL_TOLERANCE = 1, DUAL_TOLERANCE = 2 }
	Enumeration of parameters that take continuous values. More...

enum	IntegerParam { PRESOLVE = 1000, LP_ALGORITHM = 1001, INCREMENTALITY = 1002, SCALING = 1003 }
	Enumeration of parameters that take integer or categorical values. More...

enum	PresolveValues { PRESOLVE_OFF = 0, PRESOLVE_ON = 1 }
	For each categorical parameter, enumeration of possible values. More...

enum	LpAlgorithmValues { DUAL = 10, PRIMAL = 11, BARRIER = 12 }
	LP algorithm to use. More...

enum	IncrementalityValues { INCREMENTALITY_OFF = 0, INCREMENTALITY_ON = 1 }
	Advanced usage: Incrementality options. More...

enum	ScalingValues { SCALING_OFF = 0, SCALING_ON = 1 }
	Advanced usage: Scaling options. More...

Public Member Functions
	MPSolverParameters ()
	The constructor sets all parameters to their default value. More...

void	SetDoubleParam (MPSolverParameters::DoubleParam param, double value)
	Sets a double parameter to a specific value. More...

void	SetIntegerParam (MPSolverParameters::IntegerParam param, int value)
	Sets a integer parameter to a specific value. More...

void	ResetDoubleParam (MPSolverParameters::DoubleParam param)
	Sets a double parameter to its default value (default value defined in MPSolverParameters if it exists, otherwise the default value defined in the underlying solver). More...

void	ResetIntegerParam (MPSolverParameters::IntegerParam param)
	Sets an integer parameter to its default value (default value defined in MPSolverParameters if it exists, otherwise the default value defined in the underlying solver). More...

void	Reset ()
	Sets all parameters to their default value. More...

double	GetDoubleParam (MPSolverParameters::DoubleParam param) const
	Returns the value of a double parameter. More...

int	GetIntegerParam (MPSolverParameters::IntegerParam param) const
	Returns the value of an integer parameter. More...

Static Public Attributes
static const double	kDefaultDoubleParamValue

static const int	kDefaultIntegerParamValue

static const double	kUnknownDoubleParamValue

static const int	kUnknownIntegerParamValue

static const double	kDefaultRelativeMipGap

static const double	kDefaultPrimalTolerance

static const double	kDefaultDualTolerance

static const PresolveValues	kDefaultPresolve

static const IncrementalityValues	kDefaultIncrementality

Member Enumeration Documentation

◆ DoubleParam

enum operations_research::MPSolverParameters::DoubleParam

Enumeration of parameters that take continuous values.

Enumerator

RELATIVE_MIP_GAP

Limit for relative MIP gap.

PRIMAL_TOLERANCE

Advanced usage: tolerance for primal feasibility of basic solutions.

This does not control the integer feasibility tolerance of integer solutions for MIP or the tolerance used during presolve.

DUAL_TOLERANCE

Advanced usage: tolerance for dual feasibility of basic solutions.

Definition at line 1307 of file linear_solver.h.

◆ IncrementalityValues

enum operations_research::MPSolverParameters::IncrementalityValues

Advanced usage: Incrementality options.

Enumerator
INCREMENTALITY_OFF	Start solve from scratch.
INCREMENTALITY_ON	Reuse results from previous solve as much as the underlying solver allows.

Definition at line 1353 of file linear_solver.h.

◆ IntegerParam

enum operations_research::MPSolverParameters::IntegerParam

Enumeration of parameters that take integer or categorical values.

Enumerator
PRESOLVE	Advanced usage: presolve mode.
LP_ALGORITHM	Algorithm to solve linear programs.
INCREMENTALITY	Advanced usage: incrementality from one solve to the next.
SCALING	Advanced usage: enable or disable matrix scaling.

Definition at line 1323 of file linear_solver.h.

◆ LpAlgorithmValues

enum operations_research::MPSolverParameters::LpAlgorithmValues

LP algorithm to use.

Enumerator
DUAL	Dual simplex.
PRIMAL	Primal simplex.
BARRIER	Barrier algorithm.

Definition at line 1343 of file linear_solver.h.

◆ PresolveValues

enum operations_research::MPSolverParameters::PresolveValues

For each categorical parameter, enumeration of possible values.

Enumerator
PRESOLVE_OFF	Presolve is off.
PRESOLVE_ON	Presolve is on.

Definition at line 1335 of file linear_solver.h.

◆ ScalingValues

enum operations_research::MPSolverParameters::ScalingValues

Advanced usage: Scaling options.

Enumerator
SCALING_OFF	Scaling is off.
SCALING_ON	Scaling is on.

Definition at line 1365 of file linear_solver.h.

Constructor & Destructor Documentation

◆ MPSolverParameters()

operations_research::MPSolverParameters::MPSolverParameters ( )

The constructor sets all parameters to their default value.

Member Function Documentation

◆ GetDoubleParam()

double operations_research::MPSolverParameters::GetDoubleParam ( MPSolverParameters::DoubleParam param ) const

Returns the value of a double parameter.

◆ GetIntegerParam()

int operations_research::MPSolverParameters::GetIntegerParam ( MPSolverParameters::IntegerParam param ) const

Returns the value of an integer parameter.

◆ Reset()

void operations_research::MPSolverParameters::Reset ( )

Sets all parameters to their default value.

◆ ResetDoubleParam()

void operations_research::MPSolverParameters::ResetDoubleParam ( MPSolverParameters::DoubleParam param )

Sets a double parameter to its default value (default value defined in MPSolverParameters if it exists, otherwise the default value defined in the underlying solver).

◆ ResetIntegerParam()

void operations_research::MPSolverParameters::ResetIntegerParam ( MPSolverParameters::IntegerParam param )

Sets an integer parameter to its default value (default value defined in MPSolverParameters if it exists, otherwise the default value defined in the underlying solver).

◆ SetDoubleParam()

void operations_research::MPSolverParameters::SetDoubleParam	(	MPSolverParameters::DoubleParam	param,
		double	value
	)

Sets a double parameter to a specific value.

◆ SetIntegerParam()

void operations_research::MPSolverParameters::SetIntegerParam	(	MPSolverParameters::IntegerParam	param,
		int	value
	)

Sets a integer parameter to a specific value.

Member Data Documentation

◆ kDefaultDoubleParamValue

const double operations_research::MPSolverParameters::kDefaultDoubleParamValue

static

Definition at line 1374 of file linear_solver.h.

◆ kDefaultDualTolerance

const double operations_research::MPSolverParameters::kDefaultDualTolerance

static

Definition at line 1388 of file linear_solver.h.

◆ kDefaultIncrementality

const IncrementalityValues operations_research::MPSolverParameters::kDefaultIncrementality

static

Definition at line 1390 of file linear_solver.h.

◆ kDefaultIntegerParamValue

const int operations_research::MPSolverParameters::kDefaultIntegerParamValue

static

Definition at line 1375 of file linear_solver.h.

◆ kDefaultPresolve

const PresolveValues operations_research::MPSolverParameters::kDefaultPresolve

static

Definition at line 1389 of file linear_solver.h.

◆ kDefaultPrimalTolerance

const double operations_research::MPSolverParameters::kDefaultPrimalTolerance

static

Definition at line 1387 of file linear_solver.h.

◆ kDefaultRelativeMipGap

const double operations_research::MPSolverParameters::kDefaultRelativeMipGap

static

Definition at line 1386 of file linear_solver.h.

◆ kUnknownDoubleParamValue

const double operations_research::MPSolverParameters::kUnknownDoubleParamValue

static

Definition at line 1378 of file linear_solver.h.

◆ kUnknownIntegerParamValue

const int operations_research::MPSolverParameters::kUnknownIntegerParamValue

static

Definition at line 1379 of file linear_solver.h.

The documentation for this class was generated from the following file:

linear_solver.h

Detailed Description

Public Types

Public Member Functions

Static Public Attributes

Member Enumeration Documentation

◆ DoubleParam

◆ IncrementalityValues

◆ IntegerParam

◆ LpAlgorithmValues

◆ PresolveValues

◆ ScalingValues

Constructor & Destructor Documentation

◆ MPSolverParameters()

Member Function Documentation

◆ GetDoubleParam()

◆ GetIntegerParam()

◆ Reset()

◆ ResetDoubleParam()

◆ ResetIntegerParam()

◆ SetDoubleParam()

◆ SetIntegerParam()

Member Data Documentation

◆ kDefaultDoubleParamValue

◆ kDefaultDualTolerance

◆ kDefaultIncrementality

◆ kDefaultIntegerParamValue

◆ kDefaultPresolve

◆ kDefaultPrimalTolerance

◆ kDefaultRelativeMipGap

◆ kUnknownDoubleParamValue

◆ kUnknownIntegerParamValue