MixedIntegerProgramTraits Concept Reference

Definition

Concept describing the set of requirements for (constrained or unconstrained) Mixed Integer Programming (MIP) problems. A model of this concept stores the integer variables, linear objective, and linear constraints (if any) and provides a method to solve the problem.

Has Models:

CGAL::Mixed_integer_program_traits<T>

CGAL::GLPK_mixed_integer_program_traits<T>

CGAL::SCIP_mixed_integer_program_traits<T>

Creation
	MixedIntegerProgramTraits ()
	Default constructor.

Operations
MixedIntegerProgramVariable *	create_variable (Variable_type type, FT lb, FT ub, const std::string &name)
	Creates a single variable, adds it to the solver, and returns its pointer. More...
std::vector< MixedIntegerProgramVariable * >	create_variables (std::size_t n)
	Creates a set of variables, adds them to the solver, and returns their pointers. More...
MixedIntegerProgramLinearConstraint *	create_constraint (FT lb, FT ub, const std::string &name)
	Creates a single linear constraint, adds it to the solver, and returns the pointer. More...
std::vector< MixedIntegerProgramLinearConstraint * >	create_constraints (std::size_t n)
	Creates a set of linear constraints, adds them to the solver, and returns their pointers. More...
MixedIntegerProgramLinearObjective *	create_objective (Sense sense)
	Creates the objective function and returns the pointer. More...
std::size_t	number_of_variables () const
	Returns the number of variables.
const std::vector< MixedIntegerProgramVariable * > &	variables () const
	Returns the variables.
std::vector< MixedIntegerProgramVariable * > &	variables ()
std::size_t	number_of_constraints () const
	Returns the number of constraints.
const std::vector< MixedIntegerProgramLinearConstraint * > &	constraints () const
	Returns the constraints.
std::vector< MixedIntegerProgramLinearConstraint * > &	constraints ()
std::size_t	number_of_continuous_variables () const
	Returns the number of continuous variables.
std::size_t	number_of_integer_variables () const
	Returns the number of integer variables.
std::size_t	number_of_binary_variables () const
	Returns the number of binary variables.
bool	is_continuous () const
	Returns true if all variables are continuous.
bool	is_mixed_integer_program () const
	Returns true if this is a mixed integer program.
bool	is_integer_program () const
	Returns true if this is an integer program.
bool	is_binary_program () const
	Returns true if binary program.
const MixedIntegerProgramLinearObjective *	objective () const
	Returns the objective.
MixedIntegerProgramLinearObjective *	objective ()
bool	solve ()
	Solves the program. Returns false if failed.
const std::vector< FT > &	solution () const
	Returns the result. More...
const std::string &	error_message () const
	Returns the error message. More...
void	clear ()
	Clears all variables, constraints, and the objective.

Member Function Documentation

create_constraint()

template<typename FT >

MixedIntegerProgramLinearConstraint* MixedIntegerProgramTraits< FT >::create_constraint	(	FT	lb,
		FT	ub,
		const std::string &	name
	)

Creates a single linear constraint, adds it to the solver, and returns the pointer.

Note

Memory is managed by the solver and will be automatically released when the solver is destroyed.

create_constraints()

template<typename FT >

std::vector<MixedIntegerProgramLinearConstraint*> MixedIntegerProgramTraits< FT >::create_constraints

(

std::size_t

n

)

Creates a set of linear constraints, adds them to the solver, and returns their pointers.

Note

(1) Constraints will be given default names, e.g., c0, c1... (2) Memory is managed by the solver and will be automatically released when the solver is destroyed.

create_objective()

template<typename FT >

MixedIntegerProgramLinearObjective* MixedIntegerProgramTraits< FT >::create_objective

(

Sense

sense

)

Creates the objective function and returns the pointer.

Note

Memory is managed by the solver and will be automatically released when the solver is destroyed.

create_variable()

template<typename FT >

MixedIntegerProgramVariable* MixedIntegerProgramTraits< FT >::create_variable	(	Variable_type	type,
		FT	lb,
		FT	ub,
		const std::string &	name
	)

Creates a single variable, adds it to the solver, and returns its pointer.

Note

Memory is managed by the solver and will be automatically released.

create_variables()

template<typename FT >

std::vector<MixedIntegerProgramVariable*> MixedIntegerProgramTraits< FT >::create_variables

(

std::size_t

n

)

Creates a set of variables, adds them to the solver, and returns their pointers.

Note

(1) Variables will be given default names, e.g., x0, x1...; (2) Memory is managed by the solver and will be automatically released when the solver is destroyed.

error_message()

template<typename FT >

const std::string& MixedIntegerProgramTraits< FT >::error_message

(

)

const

Returns the error message.

Note

This function should be called after call to solve().

solution()

template<typename FT >

const std::vector<FT>& MixedIntegerProgramTraits< FT >::solution

(

)

const

Returns the result.

Note

(1) Result is valid only if the solver succeeded. (2) Each entry in the result corresponds to the variable with the same index in the program.