#include <linear_solver.h>

Inheritance diagram for operations_research::MPSolverInterface:

Public Types
enum	SynchronizationStatus { MUST_RELOAD , MODEL_SYNCHRONIZED , SOLUTION_SYNCHRONIZED }

Public Member Functions
	MPSolverInterface (MPSolver *solver)

virtual	~MPSolverInterface ()

virtual MPSolver::ResultStatus	Solve (const MPSolverParameters &param)=0

virtual bool	SupportsDirectlySolveProto (std::atomic< bool > *) const

virtual MPSolutionResponse	DirectlySolveProto (LazyMutableCopy< MPModelRequest >, std::atomic< bool > *)

virtual void	Write (const std::string &filename)

virtual void	Reset ()=0

virtual void	SetOptimizationDirection (bool maximize)=0
	Sets the optimization direction (min/max).

virtual void	SetVariableBounds (int index, double lb, double ub)=0
	Modifies bounds of an extracted variable.

virtual void	SetVariableInteger (int index, bool integer)=0
	Modifies integrality of an extracted variable.

virtual void	SetConstraintBounds (int index, double lb, double ub)=0
	Modify bounds of an extracted variable.

virtual void	AddRowConstraint (MPConstraint *ct)=0
	Adds a linear constraint.

virtual bool	AddIndicatorConstraint (MPConstraint *const)

virtual void	AddVariable (MPVariable *var)=0
	Add a variable.

virtual void	SetCoefficient (MPConstraint constraint, const MPVariable variable, double new_value, double old_value)=0
	Changes a coefficient in a constraint.

virtual void	ClearConstraint (MPConstraint *constraint)=0
	Clears a constraint from all its terms.

virtual void	SetObjectiveCoefficient (const MPVariable *variable, double coefficient)=0
	Changes a coefficient in the linear objective.

virtual void	SetObjectiveOffset (double value)=0
	Changes the constant term in the linear objective.

virtual void	ClearObjective ()=0
	Clears the objective from all its terms.

virtual void	BranchingPriorityChangedForVariable (int)

virtual int64_t	iterations () const =0

virtual int64_t	nodes () const =0

double	best_objective_bound () const

double	objective_value () const
	Returns the objective value of the best solution found so far.

virtual MPSolver::BasisStatus	row_status (int constraint_index) const =0
	Returns the basis status of a row.

virtual MPSolver::BasisStatus	column_status (int variable_index) const =0
	Returns the basis status of a constraint.

bool	CheckSolutionIsSynchronized () const

virtual bool	CheckSolutionExists () const

bool	CheckSolutionIsSynchronizedAndExists () const
	Handy shortcut to do both checks above (it is often used).

virtual bool	IsContinuous () const =0

virtual bool	IsLP () const =0
	Returns true if the problem is continuous and linear.

virtual bool	IsMIP () const =0
	Returns true if the problem is discrete and linear.

int	last_variable_index () const
	Returns the index of the last variable extracted.

bool	variable_is_extracted (int var_index) const

void	set_variable_as_extracted (int var_index, bool extracted)

bool	constraint_is_extracted (int ct_index) const

void	set_constraint_as_extracted (int ct_index, bool extracted)

bool	quiet () const
	Returns the boolean indicating the verbosity of the solver output.

void	set_quiet (bool quiet_value)
	Sets the boolean indicating the verbosity of the solver output.

MPSolver::ResultStatus	result_status () const
	Returns the result status of the last solve.

virtual std::string	SolverVersion () const =0
	Returns a string describing the underlying solver and its version.

virtual void *	underlying_solver ()=0
	Returns the underlying solver.

virtual double	ComputeExactConditionNumber () const

virtual void	SetStartingLpBasis (const std::vector< MPSolver::BasisStatus > &, const std::vector< MPSolver::BasisStatus > &)
	See MPSolver::SetStartingLpBasis().

virtual double	infinity ()

virtual bool	InterruptSolve ()

virtual bool	NextSolution ()
	See MPSolver::NextSolution() for contract.

virtual void	SetCallback (MPCallback *)
	See MPSolver::SetCallback() for details.

virtual bool	SupportsCallbacks () const

Static Public Attributes
static constexpr int64_t	kUnknownNumberOfIterations = -1

static constexpr int64_t	kUnknownNumberOfNodes = -1

Protected Member Functions
void	ExtractModel ()
	Extracts model stored in MPSolver.

virtual void	ExtractNewVariables ()=0
	Extracts the variables that have not been extracted yet.

virtual void	ExtractNewConstraints ()=0
	Extracts the constraints that have not been extracted yet.

virtual void	ExtractObjective ()=0
	Extracts the objective.

void	ResetExtractionInformation ()
	Resets the extraction information.

void	InvalidateSolutionSynchronization ()

void	SetCommonParameters (const MPSolverParameters &param)
	Sets parameters common to LP and MIP in the underlying solver.

void	SetMIPParameters (const MPSolverParameters &param)
	Sets MIP specific parameters in the underlying solver.

virtual void	SetParameters (const MPSolverParameters &param)=0
	Sets all parameters in the underlying solver.

void	SetUnsupportedDoubleParam (MPSolverParameters::DoubleParam param)
	Sets an unsupported double parameter.

virtual void	SetUnsupportedIntegerParam (MPSolverParameters::IntegerParam param)
	Sets an unsupported integer parameter.

void	SetDoubleParamToUnsupportedValue (MPSolverParameters::DoubleParam param, double value)
	Sets a supported double parameter to an unsupported value.

virtual void	SetIntegerParamToUnsupportedValue (MPSolverParameters::IntegerParam param, int value)
	Sets a supported integer parameter to an unsupported value.

virtual void	SetRelativeMipGap (double value)=0
	Sets each parameter in the underlying solver.

virtual void	SetPrimalTolerance (double value)=0

virtual void	SetDualTolerance (double value)=0

virtual void	SetPresolveMode (int value)=0

virtual absl::Status	SetNumThreads (int num_threads)
	Sets the number of threads to be used by the solver.

virtual bool	SetSolverSpecificParametersAsString (const std::string &parameters)

virtual void	SetScalingMode (int value)=0
	Sets the scaling mode.

virtual void	SetLpAlgorithm (int value)=0

Protected Attributes
MPSolver *const	solver_

SynchronizationStatus	sync_status_
	Indicates whether the model and the solution are synchronized.

MPSolver::ResultStatus	result_status_

bool	maximize_
	Optimization direction.

int	last_constraint_index_
	Index in MPSolver::variables_ of last constraint extracted.

int	last_variable_index_
	Index in MPSolver::constraints_ of last variable extracted.

double	objective_value_
	The value of the objective function.

double	best_objective_bound_
	The value of the best objective bound. Used only for MIP solvers.

bool	quiet_
	Boolean indicator for the verbosity of the solver output.

Static Protected Attributes
static const int	kDummyVariableIndex = 0
	-------— MPSolverInterface -------—

Friends
class	MPSolver

class	MPConstraint
	To access the maximize_ bool and the MPSolver.

class	MPObjective

Detailed Description

This class wraps the actual mathematical programming solvers. Each solver (GLOP, CLP, CBC, GLPK, SCIP) has its own interface class that derives from this abstract class. This class is never directly accessed by the user.

See also: glop_interface.cc; cbc_interface.cc; clp_interface.cc; glpk_interface.cc; scip_interface.cc

Definition at line 1634 of file linear_solver.h.

Member Enumeration Documentation

◆ SynchronizationStatus

enum operations_research::MPSolverInterface::SynchronizationStatus

Enumerator
MUST_RELOAD	The underlying solver (CLP, GLPK, ...) and MPSolver are not in sync for the model nor for the solution.
MODEL_SYNCHRONIZED	The underlying solver and MPSolver are in sync for the model but not for the solution: the model has changed since the solution was computed last.
SOLUTION_SYNCHRONIZED	The underlying solver and MPSolver are in sync for the model and the solution.

Definition at line 1636 of file linear_solver.h.

Constructor & Destructor Documentation

◆ MPSolverInterface()

operations_research::MPSolverInterface::MPSolverInterface ( MPSolver * solver )

explicit

Constructor. The user will access the MPSolverInterface through the MPSolver passed as argument.

Todo: (user): Initialize objective value and bound to +/- inf (depending on optimization direction).

Definition at line 1958 of file linear_solver.cc.

◆ ~MPSolverInterface()

operations_research::MPSolverInterface::~MPSolverInterface ( )

virtual

Definition at line 1969 of file linear_solver.cc.

Member Function Documentation

◆ AddIndicatorConstraint()

virtual bool operations_research::MPSolverInterface::AddIndicatorConstraint ( MPConstraint * const )

inlinevirtual

Adds an indicator constraint. Returns true if the feature is supported by the underlying solver.

Reimplemented in operations_research::GurobiInterface, operations_research::SatInterface, and operations_research::SCIPInterface.

Definition at line 1710 of file linear_solver.h.

◆ AddRowConstraint()

virtual void operations_research::MPSolverInterface::AddRowConstraint ( MPConstraint * ct )

pure virtual

Adds a linear constraint.

Implemented in operations_research::BopInterface, operations_research::CBCInterface, operations_research::CLPInterface, operations_research::CplexInterface, operations_research::GLOPInterface, operations_research::GLPKInterface, operations_research::GurobiInterface, operations_research::HighsInterface, operations_research::KnapsackInterface, operations_research::PdlpInterface, operations_research::SatInterface, operations_research::SCIPInterface, and operations_research::XpressInterface.

◆ AddVariable()

virtual void operations_research::MPSolverInterface::AddVariable ( MPVariable * var )

pure virtual

Add a variable.

Implemented in operations_research::BopInterface, operations_research::CBCInterface, operations_research::CLPInterface, operations_research::CplexInterface, operations_research::GLOPInterface, operations_research::GLPKInterface, operations_research::GurobiInterface, operations_research::HighsInterface, operations_research::KnapsackInterface, operations_research::PdlpInterface, operations_research::SatInterface, operations_research::SCIPInterface, and operations_research::XpressInterface.

◆ best_objective_bound()

double operations_research::MPSolverInterface::best_objective_bound ( ) const

Returns the best objective bound. The problem must be discrete, otherwise it crashes, or returns trivial bound (+/- inf) in NDEBUG mode.

Special case for empty model.

Definition at line 2038 of file linear_solver.cc.

◆ BranchingPriorityChangedForVariable()

virtual void operations_research::MPSolverInterface::BranchingPriorityChangedForVariable ( int )

inlinevirtual

Reimplemented in operations_research::GurobiInterface, and operations_research::SCIPInterface.

Definition at line 1736 of file linear_solver.h.

◆ CheckSolutionExists()

bool operations_research::MPSolverInterface::CheckSolutionExists ( ) const

virtual

Checks whether a feasible solution exists. The behavior is similar to CheckSolutionIsSynchronized() above.

Default version that can be overwritten by a solver-specific version to accommodate for the quirks of each solver.

Reimplemented in operations_research::GLPKInterface.

Definition at line 2023 of file linear_solver.cc.

◆ CheckSolutionIsSynchronized()

bool operations_research::MPSolverInterface::CheckSolutionIsSynchronized ( ) const

Checks whether the solution is synchronized with the model, i.e. whether the model has changed since the solution was computed last. If it isn't, it crashes in NDEBUG, and returns false otherwise.

Definition at line 2011 of file linear_solver.cc.

◆ CheckSolutionIsSynchronizedAndExists()

bool operations_research::MPSolverInterface::CheckSolutionIsSynchronizedAndExists ( ) const

inline

Handy shortcut to do both checks above (it is often used).

Definition at line 1763 of file linear_solver.h.

◆ ClearConstraint()

virtual void operations_research::MPSolverInterface::ClearConstraint ( MPConstraint * constraint )

pure virtual

Clears a constraint from all its terms.

Implemented in operations_research::BopInterface, operations_research::CBCInterface, operations_research::CLPInterface, operations_research::CplexInterface, operations_research::GLOPInterface, operations_research::GLPKInterface, operations_research::GurobiInterface, operations_research::HighsInterface, operations_research::KnapsackInterface, operations_research::PdlpInterface, operations_research::SatInterface, operations_research::SCIPInterface, and operations_research::XpressInterface.

◆ ClearObjective()

virtual void operations_research::MPSolverInterface::ClearObjective ( )

pure virtual

Clears the objective from all its terms.

Implemented in operations_research::BopInterface, operations_research::CBCInterface, operations_research::CLPInterface, operations_research::CplexInterface, operations_research::GLOPInterface, operations_research::GLPKInterface, operations_research::GurobiInterface, operations_research::HighsInterface, operations_research::KnapsackInterface, operations_research::PdlpInterface, operations_research::SatInterface, operations_research::SCIPInterface, and operations_research::XpressInterface.

◆ column_status()

virtual MPSolver::BasisStatus operations_research::MPSolverInterface::column_status ( int variable_index ) const

pure virtual

Returns the basis status of a constraint.

Implemented in operations_research::BopInterface, operations_research::CBCInterface, operations_research::CLPInterface, operations_research::CplexInterface, operations_research::GLOPInterface, operations_research::GLPKInterface, operations_research::GurobiInterface, operations_research::HighsInterface, operations_research::KnapsackInterface, operations_research::PdlpInterface, operations_research::SatInterface, operations_research::SCIPInterface, and operations_research::XpressInterface.

◆ ComputeExactConditionNumber()

double operations_research::MPSolverInterface::ComputeExactConditionNumber ( ) const

virtual

Computes exact condition number. Only available for continuous problems and only implemented in GLPK.

Override this method in interfaces that actually support it.

Reimplemented in operations_research::CplexInterface, operations_research::GLPKInterface, operations_research::GurobiInterface, and operations_research::XpressInterface.

Definition at line 2062 of file linear_solver.cc.

◆ constraint_is_extracted()

bool operations_research::MPSolverInterface::constraint_is_extracted ( int ct_index ) const

inline

Definition at line 1789 of file linear_solver.h.

◆ DirectlySolveProto()

virtual MPSolutionResponse operations_research::MPSolverInterface::DirectlySolveProto	(	LazyMutableCopy< MPModelRequest >	,
		std::atomic< bool > *	)

inlinevirtual

Reimplemented in operations_research::GLOPInterface, operations_research::GurobiInterface, operations_research::HighsInterface, operations_research::PdlpInterface, operations_research::SatInterface, and operations_research::SCIPInterface.

Definition at line 1676 of file linear_solver.h.

◆ ExtractModel()

void operations_research::MPSolverInterface::ExtractModel ( )

protected

Extracts model stored in MPSolver.

Everything has already been extracted.

Nothing has changed since last solve.

Definition at line 1975 of file linear_solver.cc.

◆ ExtractNewConstraints()

virtual void operations_research::MPSolverInterface::ExtractNewConstraints ( )

protectedpure virtual

Extracts the constraints that have not been extracted yet.

Implemented in operations_research::BopInterface, operations_research::CBCInterface, operations_research::CLPInterface, operations_research::CplexInterface, operations_research::GLOPInterface, operations_research::GLPKInterface, operations_research::GurobiInterface, operations_research::HighsInterface, operations_research::KnapsackInterface, operations_research::PdlpInterface, operations_research::SatInterface, operations_research::SCIPInterface, and operations_research::XpressInterface.

◆ ExtractNewVariables()

virtual void operations_research::MPSolverInterface::ExtractNewVariables ( )

protectedpure virtual

Extracts the variables that have not been extracted yet.

Implemented in operations_research::BopInterface, operations_research::CBCInterface, operations_research::CLPInterface, operations_research::CplexInterface, operations_research::GLOPInterface, operations_research::GLPKInterface, operations_research::GurobiInterface, operations_research::HighsInterface, operations_research::KnapsackInterface, operations_research::PdlpInterface, operations_research::SatInterface, operations_research::SCIPInterface, and operations_research::XpressInterface.

◆ ExtractObjective()

virtual void operations_research::MPSolverInterface::ExtractObjective ( )

protectedpure virtual

Extracts the objective.

Implemented in operations_research::BopInterface, operations_research::CBCInterface, operations_research::CLPInterface, operations_research::CplexInterface, operations_research::GLOPInterface, operations_research::GLPKInterface, operations_research::GurobiInterface, operations_research::HighsInterface, operations_research::KnapsackInterface, operations_research::PdlpInterface, operations_research::SatInterface, operations_research::SCIPInterface, and operations_research::XpressInterface.

◆ infinity()

virtual double operations_research::MPSolverInterface::infinity ( )

inlinevirtual

Reimplemented in operations_research::SCIPInterface.

Definition at line 1824 of file linear_solver.h.

◆ InterruptSolve()

virtual bool operations_research::MPSolverInterface::InterruptSolve ( )

inlinevirtual

Reimplemented in operations_research::BopInterface, operations_research::GLOPInterface, operations_research::GurobiInterface, operations_research::PdlpInterface, operations_research::SatInterface, operations_research::SCIPInterface, and operations_research::XpressInterface.

Definition at line 1826 of file linear_solver.h.

◆ InvalidateSolutionSynchronization()

void operations_research::MPSolverInterface::InvalidateSolutionSynchronization ( )

protected

Change synchronization status from SOLUTION_SYNCHRONIZED to MODEL_SYNCHRONIZED. To be used for model changes.

Definition at line 2056 of file linear_solver.cc.

◆ IsContinuous()

virtual bool operations_research::MPSolverInterface::IsContinuous ( ) const

pure virtual

--— Misc --— Queries problem type. For simplicity, the distinction between continuous and discrete is based on the declaration of the user when the solver is created (example: GLPK_LINEAR_PROGRAMMING vs. GLPK_MIXED_INTEGER_PROGRAMMING), not on the actual content of the model. Returns true if the problem is continuous.

Implemented in operations_research::BopInterface, operations_research::CBCInterface, operations_research::CLPInterface, operations_research::CplexInterface, operations_research::GLOPInterface, operations_research::GLPKInterface, operations_research::GurobiInterface, operations_research::HighsInterface, operations_research::KnapsackInterface, operations_research::PdlpInterface, operations_research::SatInterface, operations_research::SCIPInterface, and operations_research::XpressInterface.

◆ IsLP()

virtual bool operations_research::MPSolverInterface::IsLP ( ) const

pure virtual

Returns true if the problem is continuous and linear.

Implemented in operations_research::BopInterface, operations_research::CBCInterface, operations_research::CLPInterface, operations_research::CplexInterface, operations_research::GLOPInterface, operations_research::GLPKInterface, operations_research::GurobiInterface, operations_research::HighsInterface, operations_research::KnapsackInterface, operations_research::PdlpInterface, operations_research::SatInterface, operations_research::SCIPInterface, and operations_research::XpressInterface.

◆ IsMIP()

virtual bool operations_research::MPSolverInterface::IsMIP ( ) const

pure virtual

Returns true if the problem is discrete and linear.

Implemented in operations_research::BopInterface, operations_research::CBCInterface, operations_research::CLPInterface, operations_research::CplexInterface, operations_research::GLOPInterface, operations_research::GLPKInterface, operations_research::GurobiInterface, operations_research::HighsInterface, operations_research::KnapsackInterface, operations_research::PdlpInterface, operations_research::SatInterface, operations_research::SCIPInterface, and operations_research::XpressInterface.

◆ iterations()

virtual int64_t operations_research::MPSolverInterface::iterations ( ) const

pure virtual

---— Query statistics on the solution and the solve ---— Returns the number of simplex iterations. The problem must be discrete, otherwise it crashes, or returns kUnknownNumberOfIterations in NDEBUG mode.

Implemented in operations_research::BopInterface, operations_research::CBCInterface, operations_research::CLPInterface, operations_research::CplexInterface, operations_research::GLOPInterface, operations_research::GLPKInterface, operations_research::GurobiInterface, operations_research::HighsInterface, operations_research::KnapsackInterface, operations_research::PdlpInterface, operations_research::SatInterface, operations_research::SCIPInterface, and operations_research::XpressInterface.

◆ last_variable_index()

int operations_research::MPSolverInterface::last_variable_index ( ) const

inline

Returns the index of the last variable extracted.

Definition at line 1781 of file linear_solver.h.

◆ NextSolution()

virtual bool operations_research::MPSolverInterface::NextSolution ( )

inlinevirtual

See MPSolver::NextSolution() for contract.

Reimplemented in operations_research::GurobiInterface, and operations_research::SCIPInterface.

Definition at line 1829 of file linear_solver.h.

◆ nodes()

virtual int64_t operations_research::MPSolverInterface::nodes ( ) const

pure virtual

Returns the number of branch-and-bound nodes. The problem must be discrete, otherwise it crashes, or returns kUnknownNumberOfNodes in NDEBUG mode.

Implemented in operations_research::BopInterface, operations_research::CBCInterface, operations_research::CLPInterface, operations_research::CplexInterface, operations_research::GLOPInterface, operations_research::GLPKInterface, operations_research::GurobiInterface, operations_research::HighsInterface, operations_research::KnapsackInterface, operations_research::PdlpInterface, operations_research::SatInterface, operations_research::SCIPInterface, and operations_research::XpressInterface.

◆ objective_value()

double operations_research::MPSolverInterface::objective_value ( ) const

Returns the objective value of the best solution found so far.

Definition at line 2033 of file linear_solver.cc.

◆ quiet()

bool operations_research::MPSolverInterface::quiet ( ) const

inline

Returns the boolean indicating the verbosity of the solver output.

Definition at line 1797 of file linear_solver.h.

◆ Reset()

virtual void operations_research::MPSolverInterface::Reset ( )

pure virtual

--— Model modifications and extraction --— Resets extracted model.

Implemented in operations_research::BopInterface, operations_research::CBCInterface, operations_research::CLPInterface, operations_research::CplexInterface, operations_research::GLOPInterface, operations_research::GLPKInterface, operations_research::GurobiInterface, operations_research::HighsInterface, operations_research::KnapsackInterface, operations_research::PdlpInterface, operations_research::SatInterface, operations_research::SCIPInterface, and operations_research::XpressInterface.

◆ ResetExtractionInformation()

void operations_research::MPSolverInterface::ResetExtractionInformation ( )

protected

Resets the extraction information.

Todo: (user): remove this method.

Definition at line 2003 of file linear_solver.cc.

◆ result_status()

MPSolver::ResultStatus operations_research::MPSolverInterface::result_status ( ) const

inline

Returns the result status of the last solve.

Definition at line 1802 of file linear_solver.h.

◆ row_status()

virtual MPSolver::BasisStatus operations_research::MPSolverInterface::row_status ( int constraint_index ) const

pure virtual

Returns the basis status of a row.

Implemented in operations_research::BopInterface, operations_research::CBCInterface, operations_research::CLPInterface, operations_research::CplexInterface, operations_research::GLOPInterface, operations_research::GLPKInterface, operations_research::GurobiInterface, operations_research::HighsInterface, operations_research::KnapsackInterface, operations_research::PdlpInterface, operations_research::SatInterface, operations_research::SCIPInterface, and operations_research::XpressInterface.

◆ set_constraint_as_extracted()

void operations_research::MPSolverInterface::set_constraint_as_extracted	(	int	ct_index,
		bool	extracted )

inline

Definition at line 1792 of file linear_solver.h.

◆ set_quiet()

void operations_research::MPSolverInterface::set_quiet ( bool quiet_value )

inline

Sets the boolean indicating the verbosity of the solver output.

Definition at line 1799 of file linear_solver.h.

◆ set_variable_as_extracted()

void operations_research::MPSolverInterface::set_variable_as_extracted	(	int	var_index,
		bool	extracted )

inline

Definition at line 1786 of file linear_solver.h.

◆ SetCallback()

virtual void operations_research::MPSolverInterface::SetCallback ( MPCallback * )

inlinevirtual

See MPSolver::SetCallback() for details.

Reimplemented in operations_research::GurobiInterface, operations_research::SCIPInterface, and operations_research::XpressInterface.

Definition at line 1832 of file linear_solver.h.

◆ SetCoefficient()

virtual void operations_research::MPSolverInterface::SetCoefficient	(	MPConstraint *	constraint,
		const MPVariable *	variable,
		double	new_value,
		double	old_value )

pure virtual

Changes a coefficient in a constraint.

Implemented in operations_research::BopInterface, operations_research::CBCInterface, operations_research::CLPInterface, operations_research::CplexInterface, operations_research::GLOPInterface, operations_research::GLPKInterface, operations_research::GurobiInterface, operations_research::HighsInterface, operations_research::KnapsackInterface, operations_research::PdlpInterface, operations_research::SatInterface, operations_research::SCIPInterface, and operations_research::XpressInterface.

◆ SetCommonParameters()

void operations_research::MPSolverInterface::SetCommonParameters ( const MPSolverParameters & param )

protected

Sets parameters common to LP and MIP in the underlying solver.

Todo: (user): Overhaul the code that sets parameters to enable changing GLOP parameters without issuing warnings. By default, we let GLOP keep its own default tolerance, much more accurate than for the rest of the solvers.

Todo: (user): In the future, we could distinguish between the algorithm to solve the root LP and the algorithm to solve node LPs. Not sure if underlying solvers support it.

Definition at line 2071 of file linear_solver.cc.

◆ SetConstraintBounds()

virtual void operations_research::MPSolverInterface::SetConstraintBounds	(	int	index,
		double	lb,
		double	ub )

pure virtual

Modify bounds of an extracted variable.

Implemented in operations_research::BopInterface, operations_research::CBCInterface, operations_research::CLPInterface, operations_research::CplexInterface, operations_research::GLOPInterface, operations_research::GLPKInterface, operations_research::GurobiInterface, operations_research::HighsInterface, operations_research::KnapsackInterface, operations_research::PdlpInterface, operations_research::SatInterface, operations_research::SCIPInterface, and operations_research::XpressInterface.

◆ SetDoubleParamToUnsupportedValue()

void operations_research::MPSolverInterface::SetDoubleParamToUnsupportedValue	(	MPSolverParameters::DoubleParam	param,
		double	value )

protected

Sets a supported double parameter to an unsupported value.

Definition at line 2107 of file linear_solver.cc.

◆ SetDualTolerance()

virtual void operations_research::MPSolverInterface::SetDualTolerance ( double value )

protectedpure virtual

Implemented in operations_research::BopInterface, operations_research::CplexInterface, operations_research::GLOPInterface, operations_research::HighsInterface, operations_research::KnapsackInterface, operations_research::PdlpInterface, operations_research::SatInterface, and operations_research::XpressInterface.

◆ SetIntegerParamToUnsupportedValue()

void operations_research::MPSolverInterface::SetIntegerParamToUnsupportedValue	(	MPSolverParameters::IntegerParam	param,
		int	value )

protectedvirtual

Sets a supported integer parameter to an unsupported value.

Definition at line 2112 of file linear_solver.cc.

◆ SetLpAlgorithm()

virtual void operations_research::MPSolverInterface::SetLpAlgorithm ( int value )

protectedpure virtual

Implemented in operations_research::BopInterface, operations_research::CplexInterface, operations_research::GLOPInterface, operations_research::HighsInterface, operations_research::KnapsackInterface, operations_research::PdlpInterface, operations_research::SatInterface, and operations_research::XpressInterface.

◆ SetMIPParameters()

void operations_research::MPSolverInterface::SetMIPParameters ( const MPSolverParameters & param )

protected

Sets MIP specific parameters in the underlying solver.

Definition at line 2092 of file linear_solver.cc.

◆ SetNumThreads()

absl::Status operations_research::MPSolverInterface::SetNumThreads ( int num_threads )

protectedvirtual

Sets the number of threads to be used by the solver.

Reimplemented in operations_research::CBCInterface, operations_research::HighsInterface, operations_research::PdlpInterface, and operations_research::SatInterface.

Definition at line 2118 of file linear_solver.cc.

◆ SetObjectiveCoefficient()

virtual void operations_research::MPSolverInterface::SetObjectiveCoefficient	(	const MPVariable *	variable,
		double	coefficient )

pure virtual

Changes a coefficient in the linear objective.

Implemented in operations_research::BopInterface, operations_research::CBCInterface, operations_research::CLPInterface, operations_research::CplexInterface, operations_research::GLOPInterface, operations_research::GLPKInterface, operations_research::GurobiInterface, operations_research::HighsInterface, operations_research::KnapsackInterface, operations_research::PdlpInterface, operations_research::SatInterface, operations_research::SCIPInterface, and operations_research::XpressInterface.

◆ SetObjectiveOffset()

virtual void operations_research::MPSolverInterface::SetObjectiveOffset ( double value )

pure virtual

Changes the constant term in the linear objective.

Implemented in operations_research::BopInterface, operations_research::CBCInterface, operations_research::CLPInterface, operations_research::CplexInterface, operations_research::GLOPInterface, operations_research::GLPKInterface, operations_research::GurobiInterface, operations_research::HighsInterface, operations_research::KnapsackInterface, operations_research::PdlpInterface, operations_research::SatInterface, operations_research::SCIPInterface, and operations_research::XpressInterface.

◆ SetOptimizationDirection()

virtual void operations_research::MPSolverInterface::SetOptimizationDirection ( bool maximize )

pure virtual

Sets the optimization direction (min/max).

Implemented in operations_research::BopInterface, operations_research::CBCInterface, operations_research::CLPInterface, operations_research::CplexInterface, operations_research::GLOPInterface, operations_research::GLPKInterface, operations_research::GurobiInterface, operations_research::HighsInterface, operations_research::KnapsackInterface, operations_research::PdlpInterface, operations_research::SatInterface, operations_research::SCIPInterface, and operations_research::XpressInterface.

◆ SetParameters()

virtual void operations_research::MPSolverInterface::SetParameters ( const MPSolverParameters & param )

protectedpure virtual

Sets all parameters in the underlying solver.

Implemented in operations_research::BopInterface, operations_research::CplexInterface, operations_research::GLOPInterface, operations_research::HighsInterface, operations_research::KnapsackInterface, operations_research::PdlpInterface, operations_research::SatInterface, and operations_research::XpressInterface.

◆ SetPresolveMode()

virtual void operations_research::MPSolverInterface::SetPresolveMode ( int value )

protectedpure virtual

Implemented in operations_research::BopInterface, operations_research::CplexInterface, operations_research::GLOPInterface, operations_research::HighsInterface, operations_research::KnapsackInterface, operations_research::PdlpInterface, operations_research::SatInterface, and operations_research::XpressInterface.

◆ SetPrimalTolerance()

virtual void operations_research::MPSolverInterface::SetPrimalTolerance ( double value )

protectedpure virtual

Implemented in operations_research::BopInterface, operations_research::CplexInterface, operations_research::GLOPInterface, operations_research::HighsInterface, operations_research::KnapsackInterface, operations_research::PdlpInterface, operations_research::SatInterface, and operations_research::XpressInterface.

◆ SetRelativeMipGap()

virtual void operations_research::MPSolverInterface::SetRelativeMipGap ( double value )

protectedpure virtual

Sets each parameter in the underlying solver.

Implemented in operations_research::BopInterface, operations_research::CplexInterface, operations_research::GLOPInterface, operations_research::HighsInterface, operations_research::KnapsackInterface, operations_research::PdlpInterface, operations_research::SatInterface, and operations_research::XpressInterface.

◆ SetScalingMode()

virtual void operations_research::MPSolverInterface::SetScalingMode ( int value )

protectedpure virtual

Sets the scaling mode.

Implemented in operations_research::BopInterface, operations_research::CplexInterface, operations_research::GLOPInterface, operations_research::HighsInterface, operations_research::KnapsackInterface, operations_research::PdlpInterface, operations_research::SatInterface, and operations_research::XpressInterface.

◆ SetSolverSpecificParametersAsString()

bool operations_research::MPSolverInterface::SetSolverSpecificParametersAsString ( const std::string & parameters )

protectedvirtual

Pass solver specific parameters in text format. The format is solver-specific and is the same as the corresponding solver configuration file format. Returns true if the operation was successful.

Default implementation returns true if the input is empty. It returns false and logs a WARNING if the input is not empty.

Reimplemented in operations_research::BopInterface, operations_research::CplexInterface, operations_research::GLOPInterface, operations_research::HighsInterface, operations_research::PdlpInterface, and operations_research::SatInterface.

Definition at line 2123 of file linear_solver.cc.

◆ SetStartingLpBasis()

virtual void operations_research::MPSolverInterface::SetStartingLpBasis	(	const std::vector< MPSolver::BasisStatus > &	,
		const std::vector< MPSolver::BasisStatus > &	)

inlinevirtual

See MPSolver::SetStartingLpBasis().

Reimplemented in operations_research::GLOPInterface, and operations_research::XpressInterface.

Definition at line 1818 of file linear_solver.h.

◆ SetUnsupportedDoubleParam()

void operations_research::MPSolverInterface::SetUnsupportedDoubleParam ( MPSolverParameters::DoubleParam param )

protected

Sets an unsupported double parameter.

Definition at line 2099 of file linear_solver.cc.

◆ SetUnsupportedIntegerParam()

void operations_research::MPSolverInterface::SetUnsupportedIntegerParam ( MPSolverParameters::IntegerParam param )

protectedvirtual

Sets an unsupported integer parameter.

Definition at line 2103 of file linear_solver.cc.

◆ SetVariableBounds()

virtual void operations_research::MPSolverInterface::SetVariableBounds	(	int	index,
		double	lb,
		double	ub )

pure virtual

Modifies bounds of an extracted variable.

Implemented in operations_research::BopInterface, operations_research::CBCInterface, operations_research::CLPInterface, operations_research::CplexInterface, operations_research::GLOPInterface, operations_research::GLPKInterface, operations_research::GurobiInterface, operations_research::HighsInterface, operations_research::KnapsackInterface, operations_research::PdlpInterface, operations_research::SatInterface, operations_research::SCIPInterface, and operations_research::XpressInterface.

◆ SetVariableInteger()

virtual void operations_research::MPSolverInterface::SetVariableInteger	(	int	index,
		bool	integer )

pure virtual

Modifies integrality of an extracted variable.

Implemented in operations_research::BopInterface, operations_research::CBCInterface, operations_research::CLPInterface, operations_research::CplexInterface, operations_research::GLOPInterface, operations_research::GLPKInterface, operations_research::GurobiInterface, operations_research::HighsInterface, operations_research::KnapsackInterface, operations_research::PdlpInterface, operations_research::SatInterface, operations_research::SCIPInterface, and operations_research::XpressInterface.

◆ Solve()

virtual MPSolver::ResultStatus operations_research::MPSolverInterface::Solve ( const MPSolverParameters & param )

pure virtual

--— Solve --— Solves problem with specified parameter values. Returns true if the solution is optimal.

Implemented in operations_research::BopInterface, operations_research::CBCInterface, operations_research::CLPInterface, operations_research::CplexInterface, operations_research::GLOPInterface, operations_research::GLPKInterface, operations_research::GurobiInterface, operations_research::HighsInterface, operations_research::KnapsackInterface, operations_research::PdlpInterface, operations_research::SatInterface, operations_research::SCIPInterface, and operations_research::XpressInterface.

◆ SolverVersion()

virtual std::string operations_research::MPSolverInterface::SolverVersion ( ) const

pure virtual

Returns a string describing the underlying solver and its version.

Implemented in operations_research::BopInterface, operations_research::CBCInterface, operations_research::CLPInterface, operations_research::CplexInterface, operations_research::GLOPInterface, operations_research::GLPKInterface, operations_research::GurobiInterface, operations_research::HighsInterface, operations_research::KnapsackInterface, operations_research::PdlpInterface, operations_research::SatInterface, operations_research::SCIPInterface, and operations_research::XpressInterface.

◆ SupportsCallbacks()

virtual bool operations_research::MPSolverInterface::SupportsCallbacks ( ) const

inlinevirtual

Reimplemented in operations_research::GurobiInterface, operations_research::SCIPInterface, and operations_research::XpressInterface.

Definition at line 1836 of file linear_solver.h.

◆ SupportsDirectlySolveProto()

virtual bool operations_research::MPSolverInterface::SupportsDirectlySolveProto ( std::atomic< bool > * ) const

inlinevirtual

DirectlySolveProto() shall only be used if SupportsDirectlySolveProto() is true.

DirectlySolveProto() solves a MPModelRequest, bypassing the MPSolver data structures entirely. Like MPSolver::SolveWithProto(), optionally takes in an 'interrupt' boolean.

Reimplemented in operations_research::GLOPInterface, operations_research::GurobiInterface, operations_research::HighsInterface, operations_research::PdlpInterface, operations_research::SatInterface, and operations_research::SCIPInterface.

Definition at line 1672 of file linear_solver.h.

◆ underlying_solver()

virtual void * operations_research::MPSolverInterface::underlying_solver ( )

pure virtual

Returns the underlying solver.

Implemented in operations_research::BopInterface, operations_research::CBCInterface, operations_research::CLPInterface, operations_research::CplexInterface, operations_research::GLOPInterface, operations_research::GLPKInterface, operations_research::GurobiInterface, operations_research::HighsInterface, operations_research::KnapsackInterface, operations_research::PdlpInterface, operations_research::SatInterface, operations_research::SCIPInterface, and operations_research::XpressInterface.

◆ variable_is_extracted()

bool operations_research::MPSolverInterface::variable_is_extracted ( int var_index ) const

inline

Definition at line 1783 of file linear_solver.h.

◆ Write()

void operations_research::MPSolverInterface::Write ( const std::string & filename )

virtual

Writes the model using the solver internal write function. Currently only available for GurobiInterface and XpressInterface.

Reimplemented in operations_research::GurobiInterface, and operations_research::XpressInterface.

Definition at line 1971 of file linear_solver.cc.

Friends And Related Symbol Documentation

◆ MPConstraint

friend class MPConstraint

friend

To access the maximize_ bool and the MPSolver.

Definition at line 1841 of file linear_solver.h.

◆ MPObjective

friend class MPObjective

friend

Definition at line 1842 of file linear_solver.h.

◆ MPSolver

friend class MPSolver

friend

Definition at line 1838 of file linear_solver.h.

Member Data Documentation

◆ best_objective_bound_

double operations_research::MPSolverInterface::best_objective_bound_

protected

The value of the best objective bound. Used only for MIP solvers.

Definition at line 1863 of file linear_solver.h.

◆ kDummyVariableIndex

const int operations_research::MPSolverInterface::kDummyVariableIndex = 0

staticprotected

-------— MPSolverInterface -------—

Index of dummy variable created for empty constraints or the objective offset.

Definition at line 1870 of file linear_solver.h.

◆ kUnknownNumberOfIterations

int64_t operations_research::MPSolverInterface::kUnknownNumberOfIterations = -1

staticconstexpr

When the underlying solver does not provide the number of simplex iterations.

Definition at line 1651 of file linear_solver.h.

◆ kUnknownNumberOfNodes

int64_t operations_research::MPSolverInterface::kUnknownNumberOfNodes = -1

staticconstexpr

When the underlying solver does not provide the number of branch-and-bound nodes.

Definition at line 1654 of file linear_solver.h.

◆ last_constraint_index_

int operations_research::MPSolverInterface::last_constraint_index_

protected

Index in MPSolver::variables_ of last constraint extracted.

Definition at line 1855 of file linear_solver.h.

◆ last_variable_index_

int operations_research::MPSolverInterface::last_variable_index_

protected

Index in MPSolver::constraints_ of last variable extracted.

Definition at line 1857 of file linear_solver.h.

◆ maximize_

bool operations_research::MPSolverInterface::maximize_

protected

Optimization direction.

Definition at line 1852 of file linear_solver.h.

◆ objective_value_

double operations_research::MPSolverInterface::objective_value_

protected

The value of the objective function.

Definition at line 1860 of file linear_solver.h.

◆ quiet_

bool operations_research::MPSolverInterface::quiet_

protected

Boolean indicator for the verbosity of the solver output.

Definition at line 1866 of file linear_solver.h.

◆ result_status_

MPSolver::ResultStatus operations_research::MPSolverInterface::result_status_

protected

Indicates whether the solve has reached optimality, infeasibility, a limit, etc.

Definition at line 1850 of file linear_solver.h.

◆ solver_

MPSolver* const operations_research::MPSolverInterface::solver_

protected

Definition at line 1845 of file linear_solver.h.

◆ sync_status_

SynchronizationStatus operations_research::MPSolverInterface::sync_status_

protected

Indicates whether the model and the solution are synchronized.

Definition at line 1847 of file linear_solver.h.

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

ortools/linear_solver/linear_solver.h
ortools/linear_solver/linear_solver.cc

Public Types

Public Member Functions

Static Public Attributes

Protected Member Functions

Protected Attributes

Static Protected Attributes

Friends

Detailed Description

Member Enumeration Documentation

◆ SynchronizationStatus

Constructor & Destructor Documentation

◆ MPSolverInterface()

◆ ~MPSolverInterface()

Member Function Documentation

◆ AddIndicatorConstraint()

◆ AddRowConstraint()

◆ AddVariable()

◆ best_objective_bound()

◆ BranchingPriorityChangedForVariable()

◆ CheckSolutionExists()

◆ CheckSolutionIsSynchronized()

◆ CheckSolutionIsSynchronizedAndExists()

◆ ClearConstraint()

◆ ClearObjective()

◆ column_status()

◆ ComputeExactConditionNumber()

◆ constraint_is_extracted()

◆ DirectlySolveProto()

◆ ExtractModel()

◆ ExtractNewConstraints()

◆ ExtractNewVariables()

◆ ExtractObjective()

◆ infinity()

◆ InterruptSolve()

◆ InvalidateSolutionSynchronization()

◆ IsContinuous()

◆ IsLP()

◆ IsMIP()

◆ iterations()

◆ last_variable_index()

◆ NextSolution()

◆ nodes()

◆ objective_value()

◆ quiet()

◆ Reset()

◆ ResetExtractionInformation()

◆ result_status()

◆ row_status()

◆ set_constraint_as_extracted()

◆ set_quiet()

◆ set_variable_as_extracted()

◆ SetCallback()

◆ SetCoefficient()

◆ SetCommonParameters()

◆ SetConstraintBounds()

◆ SetDoubleParamToUnsupportedValue()

◆ SetDualTolerance()

◆ SetIntegerParamToUnsupportedValue()

◆ SetLpAlgorithm()

◆ SetMIPParameters()

◆ SetNumThreads()

◆ SetObjectiveCoefficient()

◆ SetObjectiveOffset()

◆ SetOptimizationDirection()

◆ SetParameters()

◆ SetPresolveMode()

◆ SetPrimalTolerance()

◆ SetRelativeMipGap()

◆ SetScalingMode()

◆ SetSolverSpecificParametersAsString()

◆ SetStartingLpBasis()

◆ SetUnsupportedDoubleParam()

◆ SetUnsupportedIntegerParam()

◆ SetVariableBounds()

◆ SetVariableInteger()

◆ Solve()

◆ SolverVersion()

◆ SupportsCallbacks()

◆ SupportsDirectlySolveProto()

◆ underlying_solver()