Detailed Description

Models and solves optimization problems with Gurobi.

This is a thin wrapper on the Gurobi C API, holding a GRBmodel, associated GRBenv that GRBnewmodel creates, and optionally the primary environment to clean up on deletion.

Throughout, we refer to the child GRBenv created by GRBnewmodel as the "model environment" while the GRBenv that was used to create the model as the "primary environment", for details see: https://www.gurobi.com/documentation/9.1/refman/c_newmodel.html Attributes Most properties of a Gurobi optimization model are set and read with attributes, using the attribute names defined in the Gurobi C API. There are scalar attributes returning a single value of the following types:

int, e.g. GRB_INT_ATTR_MODELSENSE
double, e.g. GRB_DBL_ATTR_OBJVAL
string, e.g. GRB_STR_ATTR_MODELNAME and array attributes returning a list of values of the following types:
int array, e.g. GRB_INT_ATTR_BRANCHPRIORITY
double array, e.g. GRB_DBL_ATTR_LB
char array, e.g. GRB_CHAR_ATTR_VTYPE

You set a scalar attribute with the methods SetXXXAttr, e.g. std::unique_ptr<Gurobi> gurobi = Gurobi::New().value(); absl::Status s = gurobi->SetIntAttr(GRB_INT_ATTR_MODELSENSE, 1);

Note: not all attributes can be set; consult the Gurobi attribute docs.

Attributes can also be read. However, attributes can be unavailable depending on the context, e.g. the solution objective value is not available before solving. You can determine when an attribute is available either from the Gurobi documentation or by directly testing: std::unique_ptr<Gurobi> gurobi = Gurobi::New().value(); bool is_avail = gurobi->IsAttrAvailable(GRB_DBL_ATTR_OBJVAL); To read an attribute: std::unique_ptr<Gurobi> gurobi = Gurobi::New().value(); absl::StatusOr<double> obj = gurobi->GetDoubleAttr(GRB_DBL_ATTR_OBJVAL); (The method should succeed when IsAttrAvailable() is true and you have specified the type of attribute correctly.)

Array attributes are similar, but the API differs slightly. E.g. to set the first three variable lower bounds to 1.0: std::unique_ptr<Gurobi> gurobi = Gurobi::New().value(); absl::Status s = gurobi->SetDoubleAttrArray(GRB_DBL_ATTR_LB, {1, 1, 1}); You can also set specific indices, see SetDoubleAttrList. To read, use: Gurobi* gurobi = ...; int num_vars = ...; absl::StatusOr<std::vector<double>> lbs = gurobi->GetDoubleAttrArray(GRB_DBL_ATTR_LB, num_vars); An overload to write the result into an absl::Span is also provided.

Warning: as with the Gurobi C API, attributes cannot be read immediately after they have been set. You need to call UpdateModel() (which is called by Optimize()) before reading the model back. E.g. std::unique_ptr<Gurobi> gurobi = Gurobi::New().value(); CHECK_OK(gurobi->AddVars({1, 1}, {0, 0}, {1, 1}, {GRB_INTEGER, GRB_INTEGER}, {"x", "y"})); int num_vars = gurobi->GetIntAttr(GRB_INT_ATTR_NUMVARS).value(); ///< Is 0. CHECK_OK(gurobi->UpdateModel()); num_vars = gurobi->GetIntAttr(GRB_INT_ATTR_NUMVARS).value(); ///< Is now 2. Calls to UpdateModel() are expensive and should be minimized. Parameters Parameters are associated directly with Gurobi rather than a GRBenv as in the C API. Parameters have three types: int, double and string. You can get and set them by their C API names, e.g. std::unique_ptr<Gurobi> gurobi = Gurobi::New().value(); gurobi->SetIntParam(GRB_INT_PAR_LOGTOCONSOLE, 1); gurobi->GetIntParam(GRB_INT_PAR_LOGTOCONSOLE); ///< Returns 1. Unlike attributes, values can be read immediately, no call to UpdateModel() is required.

Definition at line 149 of file g_gurobi.h.

#include <g_gurobi.h>

Classes
class	CallbackContext
struct	SparseMat

Public Types
using	Callback = std::function<absl::Status(const CallbackContext&)>

Public Member Functions
	~Gurobi ()
absl::Status	AddVar (double obj, double lb, double ub, char vtype, const std::string &name)
	Calls GRBaddvar() to add a variable to the model.
absl::Status	AddVar (absl::Span< const int > vind, absl::Span< const double > vval, double obj, double lb, double ub, char vtype, const std::string &name)
have size equal to the number of new be	empty (all new variables have objective coefficient 0). - have size equal to the number of new variables
have size equal to the number of new be be empty(all new variables have name ""). absl have size equal to the number of new be	empty (all new variables have objective coefficient 0). - have size equal to the number of new variables
have size equal to the number of new be be empty(all new variables have name ""). absl have size equal to the number of new be be empty(all new variables have name ""). absl absl::Status	DelVars (absl::Span< const int > ind)
	Calls GRBdelvars().
absl::Status	AddConstr (char sense, double rhs, const std::string &name)
absl::Status	AddConstr (absl::Span< const int > cind, absl::Span< const double > cval, char sense, double rhs, const std::string &name)
have size equal to the number of new be empty(all new constraints have name ""). absl absl::Status	DelConstrs (absl::Span< const int > ind)
	Calls GRBdelconstrs().
absl::Status	ChgCoeffs (absl::Span< const int > cind, absl::Span< const int > vind, absl::Span< const double > val)
absl::Status	AddQpTerms (absl::Span< const int > qrow, absl::Span< const int > qcol, absl::Span< const double > qval)
absl::Status	DelQ ()
absl::Status	SetNthObjective (int index, int priority, double weight, double abs_tol, double rel_tol, const std::string &name, double constant, absl::Span< const int > lind, absl::Span< const double > lval)
absl::Status	AddQConstr (absl::Span< const int > lind, absl::Span< const double > lval, absl::Span< const int > qrow, absl::Span< const int > qcol, absl::Span< const double > qval, char sense, double rhs, const std::string &name)
absl::Status	DelQConstrs (absl::Span< const int > ind)
absl::Status	AddSos (absl::Span< const int > types, absl::Span< const int > beg, absl::Span< const int > ind, absl::Span< const double > weight)
absl::Status	DelSos (absl::Span< const int > ind)
absl::Status	AddIndicator (const std::string &name, int binvar, int binval, absl::Span< const int > ind, absl::Span< const double > val, char sense, double rhs)
absl::Status	DelGenConstrs (absl::Span< const int > ind)
absl::StatusOr< int >	GetNnz (int first_var, int num_vars)
absl::Status	GetVars (absl::Span< int > vbegin, absl::Span< int > vind, absl::Span< double > vval, int first_var, int num_vars)
absl::StatusOr< SparseMat >	GetVars (int first_var, int num_vars)
absl::Status	UpdateModel ()
	Calls GRBupdatemodel().
absl::Status	Optimize (Callback cb=nullptr)
void	Terminate ()
	Calls GRBterminate().
absl::StatusOr< bool >	ComputeIIS (Callback cb=nullptr)
bool	IsAttrAvailable (const char *name) const
absl::StatusOr< int >	GetIntAttr (const char *name) const
absl::Status	SetIntAttr (const char *attr_name, int value)
absl::StatusOr< double >	GetDoubleAttr (const char *name) const
absl::Status	SetDoubleAttr (const char *attr_name, double value)
absl::StatusOr< std::string >	GetStringAttr (const char *name) const
absl::Status	SetStringAttr (const char *attr_name, const std::string &value)
absl::Status	GetIntAttrArray (const char *name, absl::Span< int > attr_out) const
absl::StatusOr< std::vector< int > >	GetIntAttrArray (const char *name, int len) const
absl::Status	SetIntAttrArray (const char *name, absl::Span< const int > new_values)
absl::Status	SetIntAttrList (const char *name, absl::Span< const int > ind, absl::Span< const int > new_values)
absl::Status	GetDoubleAttrArray (const char *name, absl::Span< double > attr_out) const
absl::StatusOr< std::vector< double > >	GetDoubleAttrArray (const char *name, int len) const
absl::Status	SetDoubleAttrArray (const char *name, absl::Span< const double > new_values)
absl::Status	SetDoubleAttrList (const char *name, absl::Span< const int > ind, absl::Span< const double > new_values)
absl::Status	GetCharAttrArray (const char *name, absl::Span< char > attr_out) const
absl::StatusOr< std::vector< char > >	GetCharAttrArray (const char *name, int len) const
absl::Status	SetCharAttrArray (const char *name, absl::Span< const char > new_values)
absl::Status	SetCharAttrList (const char *name, absl::Span< const int > ind, absl::Span< const char > new_values)
absl::StatusOr< int >	GetIntAttrElement (const char *name, int element) const
absl::Status	SetIntAttrElement (const char *name, int element, int new_value)
absl::StatusOr< double >	GetDoubleAttrElement (const char *name, int element) const
absl::Status	SetDoubleAttrElement (const char *name, int element, double new_value)
absl::StatusOr< char >	GetCharAttrElement (const char *name, int element) const
absl::Status	SetCharAttrElement (const char *name, int element, char new_value)
absl::Status	SetParam (const char *name, const std::string &value)
absl::Status	SetIntParam (const char *name, int value)
	Calls GRBsetintparam().
absl::Status	SetDoubleParam (const char *name, double value)
	Calls GRBsetdblparam().
absl::Status	SetStringParam (const char *name, const std::string &value)
	Calls GRBsetstrparam().
absl::StatusOr< int >	GetIntParam (const char *name)
	Calls GRBgetintparam().
absl::StatusOr< double >	GetDoubleParam (const char *name)
	Calls GRBgetdblparam().
absl::StatusOr< std::string >	GetStringParam (const char *name)
	Calls GRBgetstrparam().
absl::Status	ResetParameters ()
	Calls GRBresetparams().
absl::Status	SetMultiObjectiveDoubleParam (const char *name, int obj_index, double value)
absl::StatusOr< double >	GetMultiObjectiveDoubleParam (const char *name, int obj_index)
GRBmodel *	model () const
	Typically not needed.
absl::Status	ToStatus (int grb_err, absl::StatusCode code=absl::StatusCode::kInvalidArgument, absl::SourceLocation loc=absl::SourceLocation::current()) const

Static Public Member Functions
static absl::StatusOr< std::unique_ptr< Gurobi > >	New (GRBenvUniquePtr primary_env=nullptr)
static absl::StatusOr< std::unique_ptr< Gurobi > >	NewWithSharedPrimaryEnv (GRBenv *primary_env)

Public Attributes
have size equal to the number of new	variables
have size equal to the number of new be be empty(all new variables have name ""). absl have size equal to the number of new	variables
have size equal to the number of new	constraints

Member Typedef Documentation

◆ Callback

using operations_research::math_opt::Gurobi::Callback = std::function<absl::Status(const CallbackContext&)>

Invoked regularly by Gurobi while solving if provided as an argument to Gurobi::Optimize(). If the user returns a status error in the callback:

Termination of the solve is requested.
The error is propagated to the return value of Gurobi::Optimize().
The callback will not be invoked again.

Definition at line 222 of file g_gurobi.h.

Constructor & Destructor Documentation

◆ ~Gurobi()

operations_research::math_opt::Gurobi::~Gurobi ( )

Definition at line 227 of file g_gurobi.cc.

Member Function Documentation

◆ AddConstr() [1/2]

absl::Status operations_research::math_opt::Gurobi::AddConstr	(	absl::Span< const int >	cind,
		absl::Span< const double >	cval,
		char	sense,
		double	rhs,
		const std::string &	name )

Calls GRBaddconstr() to add a constraint to the model.

The inputs cind and cval must have the same size.

Definition at line 326 of file g_gurobi.cc.

◆ AddConstr() [2/2]

absl::Status operations_research::math_opt::Gurobi::AddConstr	(	char	sense,
		double	rhs,
		const std::string &	name )

Calls GRBaddconstr() to add a constraint to the model.

This overload does not add any variable coefficients to the constraint.

Definition at line 321 of file g_gurobi.cc.

◆ AddIndicator()

absl::Status operations_research::math_opt::Gurobi::AddIndicator	(	const std::string &	name,
		int	binvar,
		int	binval,
		absl::Span< const int >	ind,
		absl::Span< const double >	val,
		char	sense,
		double	rhs )

Calls GRBaddgenconstrIndicator().

ind and val must be of equal length.

Definition at line 460 of file g_gurobi.cc.

◆ AddQConstr()

absl::Status operations_research::math_opt::Gurobi::AddQConstr	(	absl::Span< const int >	lind,
		absl::Span< const double >	lval,
		absl::Span< const int >	qrow,
		absl::Span< const int >	qcol,
		absl::Span< const double >	qval,
		char	sense,
		double	rhs,
		const std::string &	name )

Calls GRBaddqconstr().

Requirements:

lind and lval must be equal length.
qrow, qcol, and qval must be equal length.

Definition at line 404 of file g_gurobi.cc.

◆ AddQpTerms()

absl::Status operations_research::math_opt::Gurobi::AddQpTerms	(	absl::Span< const int >	qrow,
		absl::Span< const int >	qcol,
		absl::Span< const double >	qval )

Calls GRBaddqpterms().

Requirements:

qrow, qcol, and qval have size equal to the number of new quadratic objective terms.

Definition at line 368 of file g_gurobi.cc.

◆ AddSos()

absl::Status operations_research::math_opt::Gurobi::AddSos	(	absl::Span< const int >	types,
		absl::Span< const int >	beg,
		absl::Span< const int >	ind,
		absl::Span< const double >	weight )

Calls GRBaddsos().

This adds SOS constraints to the model. You may specify multiple SOS constraints at once, and may mix the types (SOS1 and SOS2) in a single call. The data is specified in CSR format, meaning that the entries of beg indicate the contiguous subranges of ind and weight associated with a particular SOS constraint. Please see the Gurobi documentation for more detail (https://www.gurobi.com/documentation/9.5/refman/c_addsos.html).

Requirements:

types and beg must be of equal length.
ind and weight must be of equal length.

Definition at line 437 of file g_gurobi.cc.

◆ AddVar() [1/2]

absl::Status operations_research::math_opt::Gurobi::AddVar	(	absl::Span< const int >	vind,
		absl::Span< const double >	vval,
		double	obj,
		double	lb,
		double	ub,
		char	vtype,
		const std::string &	name )

Calls GRBaddvar() to add a variable and linear constraint column to the model.

The inputs vind and vval must have the same size. Both can be empty if you do not want to modify the constraint matrix, though this is equivalent to the simpler overload above.

Definition at line 251 of file g_gurobi.cc.

◆ AddVar() [2/2]

absl::Status operations_research::math_opt::Gurobi::AddVar	(	double	obj,
		double	lb,
		double	ub,
		char	vtype,
		const std::string &	name )

Calls GRBaddvar() to add a variable to the model.

Model Building

Definition at line 246 of file g_gurobi.cc.

◆ ChgCoeffs()

absl::Status operations_research::math_opt::Gurobi::ChgCoeffs	(	absl::Span< const int >	cind,
		absl::Span< const int >	vind,
		absl::Span< const double >	val )

Calls GRBchgcoeffs().

Requirements:

cind, vind, and val have size equal to the number of changed constraint matrix entries.

Definition at line 479 of file g_gurobi.cc.

◆ ComputeIIS()

absl::StatusOr< bool > operations_research::math_opt::Gurobi::ComputeIIS ( Callback cb = nullptr )

Calls GRBcomputeIIS().

Returns:

a status if Gurobi errors,
true if Gurobi proves that the model is infeasible, or
false otherwise (e.g., feasibility is proven or a limit is reached).

The callback, if specified, is set before solving and cleared after.

If Gurobi v11 terminates at a limit before determining if the model is feasible or not, it will return an OK error code but then will fail to return anything about the IIS it does not have. To detect this case, we query the minimality attribute: we know that our env is valid at this point, and this should fail iff an IIS is present, i.e., Gurobi proved that the model was infeasible.

Definition at line 538 of file g_gurobi.cc.

◆ DelConstrs()

absl::Status operations_research::math_opt::Gurobi::DelConstrs ( absl::Span< const int > ind )

Calls GRBdelconstrs().

Definition at line 363 of file g_gurobi.cc.

◆ DelGenConstrs()

absl::Status operations_research::math_opt::Gurobi::DelGenConstrs ( absl::Span< const int > ind )

Calls GRBdelgenconstrs().

Deletes the specified general constraints.

Definition at line 474 of file g_gurobi.cc.

◆ DelQ()

absl::Status operations_research::math_opt::Gurobi::DelQ ( )

Calls GRBdelq().

Deletes all quadratic objective coefficients.

Definition at line 379 of file g_gurobi.cc.

◆ DelQConstrs()

absl::Status operations_research::math_opt::Gurobi::DelQConstrs ( absl::Span< const int > ind )

Calls GRBdelqconstrs().

Deletes the specified quadratic constraints.

Definition at line 432 of file g_gurobi.cc.

◆ DelSos()

absl::Status operations_research::math_opt::Gurobi::DelSos ( absl::Span< const int > ind )

Calls GRBdelsos().

Deletes the specified SOS constraints.

Definition at line 455 of file g_gurobi.cc.

◆ DelVars()

absl::Status operations_research::math_opt::Gurobi::DelVars ( absl::Span< const int > ind )

Calls GRBdelvars().

vbegin should have size equal to the number of new variables.
- vind and vsize should have size equal to the number of new nonzeros in the linear constraint matrix.
  Note
  vbegin, vind and vval can all be empty if you do not want to modify the constraint matrix, this is equivalent to the simpler overload above.

Definition at line 316 of file g_gurobi.cc.

◆ empty() [1/2]

have size equal to the number of new be operations_research::math_opt::Gurobi::empty ( all new variables have objective coefficient 0 )

new

names should either:

◆ empty() [2/2]

have size equal to the number of new be be empty(all new variables have name ""). absl have size equal to the number of new be operations_research::math_opt::Gurobi::empty ( all new variables have objective coefficient 0 )

new

names should either:

◆ GetCharAttrArray() [1/2]

absl::Status operations_research::math_opt::Gurobi::GetCharAttrArray	(	const char *	name,
		absl::Span< char >	attr_out ) const

Definition at line 653 of file g_gurobi.cc.

◆ GetCharAttrArray() [2/2]

absl::StatusOr< std::vector< char > > operations_research::math_opt::Gurobi::GetCharAttrArray	(	const char *	name,
		int	len ) const

Definition at line 661 of file g_gurobi.cc.

◆ GetCharAttrElement()

absl::StatusOr< char > operations_research::math_opt::Gurobi::GetCharAttrElement	(	const char *	name,
		int	element ) const

Definition at line 726 of file g_gurobi.cc.

◆ GetDoubleAttr()

absl::StatusOr< double > operations_research::math_opt::Gurobi::GetDoubleAttr ( const char * name ) const

Definition at line 571 of file g_gurobi.cc.

◆ GetDoubleAttrArray() [1/2]

absl::Status operations_research::math_opt::Gurobi::GetDoubleAttrArray	(	const char *	name,
		absl::Span< double >	attr_out ) const

Definition at line 638 of file g_gurobi.cc.

◆ GetDoubleAttrArray() [2/2]

absl::StatusOr< std::vector< double > > operations_research::math_opt::Gurobi::GetDoubleAttrArray	(	const char *	name,
		int	len ) const

Definition at line 646 of file g_gurobi.cc.

◆ GetDoubleAttrElement()

absl::StatusOr< double > operations_research::math_opt::Gurobi::GetDoubleAttrElement	(	const char *	name,
		int	element ) const

Definition at line 712 of file g_gurobi.cc.

◆ GetDoubleParam()

absl::StatusOr< double > operations_research::math_opt::Gurobi::GetDoubleParam ( const char * name )

Calls GRBgetdblparam().

Definition at line 766 of file g_gurobi.cc.

◆ GetIntAttr()

absl::StatusOr< int > operations_research::math_opt::Gurobi::GetIntAttr ( const char * name ) const

Definition at line 564 of file g_gurobi.cc.

◆ GetIntAttrArray() [1/2]

absl::Status operations_research::math_opt::Gurobi::GetIntAttrArray	(	const char *	name,
		absl::Span< int >	attr_out ) const

Definition at line 623 of file g_gurobi.cc.

◆ GetIntAttrArray() [2/2]

absl::StatusOr< std::vector< int > > operations_research::math_opt::Gurobi::GetIntAttrArray	(	const char *	name,
		int	len ) const

Definition at line 631 of file g_gurobi.cc.

◆ GetIntAttrElement()

absl::StatusOr< int > operations_research::math_opt::Gurobi::GetIntAttrElement	(	const char *	name,
		int	element ) const

Definition at line 698 of file g_gurobi.cc.

◆ GetIntParam()

absl::StatusOr< int > operations_research::math_opt::Gurobi::GetIntParam ( const char * name )

Calls GRBgetintparam().

Definition at line 760 of file g_gurobi.cc.

◆ GetMultiObjectiveDoubleParam()

absl::StatusOr< double > operations_research::math_opt::Gurobi::GetMultiObjectiveDoubleParam	(	const char *	name,
		int	obj_index )

Calls GRBgetdblparam() on the environment associated with the obj_index-th objective.

Definition at line 790 of file g_gurobi.cc.

◆ GetNnz()

absl::StatusOr< int > operations_research::math_opt::Gurobi::GetNnz	(	int	first_var,
		int	num_vars )

Linear constraint matrix queries. Calls GRBgetvars().

The number of nonzeros in the constraint matrix for the num_vars columns starting with first_var.

Warning: will not reflect pending modifications, call UpdateModel() or Optimize() first.

Definition at line 490 of file g_gurobi.cc.

◆ GetStringAttr()

absl::StatusOr< std::string > operations_research::math_opt::Gurobi::GetStringAttr ( const char * name ) const

Warning: if a string attribute is the empty string, we need to be careful, std::string(char*) cannot take a nullptr.

Definition at line 578 of file g_gurobi.cc.

◆ GetStringParam()

absl::StatusOr< std::string > operations_research::math_opt::Gurobi::GetStringParam ( const char * name )

Calls GRBgetstrparam().

Definition at line 772 of file g_gurobi.cc.

◆ GetVars() [1/2]

absl::Status operations_research::math_opt::Gurobi::GetVars	(	absl::Span< int >	vbegin,
		absl::Span< int >	vind,
		absl::Span< double >	vval,
		int	first_var,
		int	num_vars )

Calls GRBgetvars().

Write the nonzeros of the constraint matrix for the num_vars columns starting with first_var out in CSC format to (vbegin, vind, vval).

The user is responsible for ensuring that the output Spans are exactly the correct size. See the other GetVars() overload for a simpler version.

Warning: will not reflect pending modifications, call UpdateModel() or Optimize() first.

Definition at line 497 of file g_gurobi.cc.

◆ GetVars() [2/2]

absl::StatusOr< Gurobi::SparseMat > operations_research::math_opt::Gurobi::GetVars	(	int	first_var,
		int	num_vars )

Calls GRBgetvars().

Returns the nonzeros of the constraint matrix for the num_vars columns starting with first_var out in CSC format.

Warning: will not reflect pending modifications, call UpdateModel() or Optimize() first.

Definition at line 511 of file g_gurobi.cc.

◆ IsAttrAvailable()

bool operations_research::math_opt::Gurobi::IsAttrAvailable ( const char * name ) const

Attributes

Definition at line 560 of file g_gurobi.cc.

◆ model()

GRBmodel * operations_research::math_opt::Gurobi::model ( ) const

inline

Typically not needed.

Definition at line 590 of file g_gurobi.h.

◆ New()

absl::StatusOr< std::unique_ptr< Gurobi > > operations_research::math_opt::Gurobi::New ( GRBenvUniquePtr primary_env = nullptr )

static

Creates a new Gurobi, taking ownership of primary_env if provided (if no environment is given, a new one is created internally from the license file).

Definition at line 183 of file g_gurobi.cc.

◆ NewWithSharedPrimaryEnv()

absl::StatusOr< std::unique_ptr< Gurobi > > operations_research::math_opt::Gurobi::NewWithSharedPrimaryEnv ( GRBenv * primary_env )

static

Creates a new Gurobi using an existing GRBenv, where primary_env cannot be nullptr. Unlike Gurobi::New(), the returned Gurobi will not clean up the primary environment on destruction.

A GurobiEnv can be shared between models with the following restrictions:

Environments are not thread-safe (so use one thread or mutual exclusion for Gurobi::New()).
The primary environment must outlive each Gurobi instance.
Every "primary" environment counts as a "use" of a Gurobi License. Depending on your license type, you may need to share to run concurrent solves in the same process.

Definition at line 177 of file g_gurobi.cc.

◆ Optimize()

absl::Status operations_research::math_opt::Gurobi::Optimize ( Callback cb = nullptr )

Calls GRBoptimize().

The callback, if specified, is set before solving and cleared after.

Definition at line 530 of file g_gurobi.cc.

◆ ResetParameters()

absl::Status operations_research::math_opt::Gurobi::ResetParameters ( )

Calls GRBresetparams().

Definition at line 778 of file g_gurobi.cc.

◆ SetCharAttrArray()

absl::Status operations_research::math_opt::Gurobi::SetCharAttrArray	(	const char *	name,
		absl::Span< const char >	new_values )

Definition at line 617 of file g_gurobi.cc.

◆ SetCharAttrElement()

absl::Status operations_research::math_opt::Gurobi::SetCharAttrElement	(	const char *	name,
		int	element,
		char	new_value )

Definition at line 734 of file g_gurobi.cc.

◆ SetCharAttrList()

absl::Status operations_research::math_opt::Gurobi::SetCharAttrList	(	const char *	name,
		absl::Span< const int >	ind,
		absl::Span< const char >	new_values )

Definition at line 688 of file g_gurobi.cc.

◆ SetDoubleAttr()

absl::Status operations_research::math_opt::Gurobi::SetDoubleAttr	(	const char *	attr_name,
		double	value )

Definition at line 600 of file g_gurobi.cc.

◆ SetDoubleAttrArray()

absl::Status operations_research::math_opt::Gurobi::SetDoubleAttrArray	(	const char *	name,
		absl::Span< const double >	new_values )

Definition at line 611 of file g_gurobi.cc.

◆ SetDoubleAttrElement()

absl::Status operations_research::math_opt::Gurobi::SetDoubleAttrElement	(	const char *	name,
		int	element,
		double	new_value )

Definition at line 720 of file g_gurobi.cc.

◆ SetDoubleAttrList()

absl::Status operations_research::math_opt::Gurobi::SetDoubleAttrList	(	const char *	name,
		absl::Span< const int >	ind,
		absl::Span< const double >	new_values )

Definition at line 678 of file g_gurobi.cc.

◆ SetDoubleParam()

absl::Status operations_research::math_opt::Gurobi::SetDoubleParam	(	const char *	name,
		double	value )

Calls GRBsetdblparam().

Definition at line 750 of file g_gurobi.cc.

◆ SetIntAttr()

absl::Status operations_research::math_opt::Gurobi::SetIntAttr	(	const char *	attr_name,
		int	value )

Definition at line 596 of file g_gurobi.cc.

◆ SetIntAttrArray()

absl::Status operations_research::math_opt::Gurobi::SetIntAttrArray	(	const char *	name,
		absl::Span< const int >	new_values )

Definition at line 605 of file g_gurobi.cc.

◆ SetIntAttrElement()

absl::Status operations_research::math_opt::Gurobi::SetIntAttrElement	(	const char *	name,
		int	element,
		int	new_value )

Definition at line 706 of file g_gurobi.cc.

◆ SetIntAttrList()

absl::Status operations_research::math_opt::Gurobi::SetIntAttrList	(	const char *	name,
		absl::Span< const int >	ind,
		absl::Span< const int >	new_values )

Definition at line 668 of file g_gurobi.cc.

◆ SetIntParam()

absl::Status operations_research::math_opt::Gurobi::SetIntParam	(	const char *	name,
		int	value )

Calls GRBsetintparam().

Definition at line 746 of file g_gurobi.cc.

◆ SetMultiObjectiveDoubleParam()

absl::Status operations_research::math_opt::Gurobi::SetMultiObjectiveDoubleParam	(	const char *	name,
		int	obj_index,
		double	value )

Multi-objective Parameters Calls GRBsetdblparam() on the environment associated with the obj_index-th objective.

Definition at line 782 of file g_gurobi.cc.

◆ SetNthObjective()

absl::Status operations_research::math_opt::Gurobi::SetNthObjective	(	int	index,
		int	priority,
		double	weight,
		double	abs_tol,
		double	rel_tol,
		const std::string &	name,
		double	constant,
		absl::Span< const int >	lind,
		absl::Span< const double >	lval )

Calls GRBsetobjectiven().

Sets the n-th objective in a multi-objective model.

Requirement:

lind and lval must be of equal length.

Definition at line 381 of file g_gurobi.cc.

◆ SetParam()

absl::Status operations_research::math_opt::Gurobi::SetParam	(	const char *	name,
		const std::string &	value )

Parameters Calls GRBsetparam().

Prefer the typed versions (e.g. SetIntParam()) defined below.

Definition at line 741 of file g_gurobi.cc.

◆ SetStringAttr()

absl::Status operations_research::math_opt::Gurobi::SetStringAttr	(	const char *	attr_name,
		const std::string &	value )

Definition at line 591 of file g_gurobi.cc.

◆ SetStringParam()

absl::Status operations_research::math_opt::Gurobi::SetStringParam	(	const char *	name,
		const std::string &	value )

Calls GRBsetstrparam().

Definition at line 755 of file g_gurobi.cc.

◆ Terminate()

void operations_research::math_opt::Gurobi::Terminate ( )

Calls GRBterminate().

Definition at line 799 of file g_gurobi.cc.

◆ ToStatus()

absl::Status operations_research::math_opt::Gurobi::ToStatus	(	int	grb_err,
		absl::StatusCode	code = absl::StatusCode::kInvalidArgument,
		absl::SourceLocation	loc = absl::SourceLocation::current() ) const

Definition at line 235 of file g_gurobi.cc.

◆ UpdateModel()

absl::Status operations_research::math_opt::Gurobi::UpdateModel ( )

Calls GRBupdatemodel().

Solving

Definition at line 526 of file g_gurobi.cc.

Member Data Documentation

◆ constraints

have size equal to the number of new operations_research::math_opt::Gurobi::constraints

Calls GRBaddconstrs().

Requirements:

sense and rhs must have size equal to the number of new constraints.
names should either:

Definition at line 327 of file g_gurobi.h.

◆ variables [1/2]

have size equal to the number of new operations_research::math_opt::Gurobi::variables

Calls GRBaddvars() to add variables to the model.

Requirements:

lb, ub and vtype must have size equal to the number of new variables.
obj should either:

Definition at line 271 of file g_gurobi.h.

◆ variables [2/2]

have size equal to the number of new be be empty (all new variables have name ""). absl have size equal to the number of new operations_research::math_opt::Gurobi::variables

Calls GRBaddvars() to add variables and linear constraint columns to the model.

The new linear constraint matrix columns are given in CSC format (see SparseMat above for an example).

Requirements:

lb, ub and vtype must have size equal to the number of new variables.
obj should either:

Definition at line 290 of file g_gurobi.h.

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

ortools/math_opt/solvers/gurobi/g_gurobi.h
ortools/math_opt/solvers/gurobi/g_gurobi.cc

Detailed Description

Classes

Public Types

Public Member Functions

Static Public Member Functions

Public Attributes

Member Typedef Documentation

◆ Callback

Constructor & Destructor Documentation

◆ ~Gurobi()

Member Function Documentation

◆ AddConstr() [1/2]

◆ AddConstr() [2/2]

◆ AddIndicator()

◆ AddQConstr()

◆ AddQpTerms()

◆ AddSos()

◆ AddVar() [1/2]

◆ AddVar() [2/2]

◆ ChgCoeffs()

◆ ComputeIIS()

◆ DelConstrs()

◆ DelGenConstrs()

◆ DelQ()

◆ DelQConstrs()

◆ DelSos()

◆ DelVars()

◆ empty() [1/2]

◆ empty() [2/2]

◆ GetCharAttrArray() [1/2]

◆ GetCharAttrArray() [2/2]

◆ GetCharAttrElement()

◆ GetDoubleAttr()

◆ GetDoubleAttrArray() [1/2]

◆ GetDoubleAttrArray() [2/2]

◆ GetDoubleAttrElement()

◆ GetDoubleParam()

◆ GetIntAttr()

◆ GetIntAttrArray() [1/2]

◆ GetIntAttrArray() [2/2]

◆ GetIntAttrElement()

◆ GetIntParam()

◆ GetMultiObjectiveDoubleParam()

◆ GetNnz()

◆ GetStringAttr()

◆ GetStringParam()

◆ GetVars() [1/2]

◆ GetVars() [2/2]

◆ IsAttrAvailable()

◆ model()

◆ New()

◆ NewWithSharedPrimaryEnv()

◆ Optimize()

◆ ResetParameters()

◆ SetCharAttrArray()

◆ SetCharAttrElement()

◆ SetCharAttrList()

◆ SetDoubleAttr()

◆ SetDoubleAttrArray()

◆ SetDoubleAttrElement()

◆ SetDoubleAttrList()

◆ SetDoubleParam()

◆ SetIntAttr()

◆ SetIntAttrArray()

◆ SetIntAttrElement()

◆ SetIntAttrList()

◆ SetIntParam()

◆ SetMultiObjectiveDoubleParam()

◆ SetNthObjective()

◆ SetParam()

◆ SetStringAttr()

◆ SetStringParam()

◆ Terminate()

◆ ToStatus()

◆ UpdateModel()

Member Data Documentation

◆ constraints

◆ variables [1/2]

◆ variables [2/2]