SCIL::subproblem Class Reference

#include <subproblem.h>

List of all members.

Modifying the linear program.
*var	add_variable (double obj, double lBound, double uBound, Vartype, Activation a=Static)
void	add_variable (var, Activation a=Static)
*virtual cons	add_basic_constraint (cons_sense, double, Activation a=Dynamic)
virtual cons	add_basic_constraint (cons_obj *c, Activation a=Dynamic)
void	add_sym_constraint (sym_constraint *c)
	adds a symbolic constraint to the current node of the BCP-Tree
void	remove_variable (var V)
void	set_coefficient (var v, cons i, double d)
Inspection of the current node.
var	get_var (int i)
	returns the variable with index i.
int	nVar () const
	returns the number of active variables in the current node.
double	get_coeff (var v, cons i)
	returns the coefficient of the LP-matrix for v and \i
int	first_variable_item () const
	Returns the index of the first variable.
int	next_variable_item (int i) const
	returns the index of the variable succeding the variable with index i.
int	next_constraint_item (int i) const
	returns the index of the variable succeding the variable with index i.
cons	get_cons (int i)
	returns the basic constraint with index i
int	ncons ()
	returns the number of basic constraints in the current LP.
virtual double	value (var v)
	returns the value of v of the last solved LP.
double	value (row &r)
	returns the value of r of the last solved LP.
double	lower_bound (var v)
	returns the lower bound of the variable in the current node.
double	upper_bound (var v)
	returns the upper bound of the variable in the current node.
double	value (cons i, as_what as=as_is)
double	red_cost (var v)
	returns the value of v of the last solved LP.
Configurations.
const LEDA::string &	configuration (const LEDA::string &s) const
	returns the configuration for s.
LEDA::string &	configuration (const LEDA::string &)
	sets the configuration for s.

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Detailed Description

Subproblem - A node in the branch & cut tree

Definition at line 38 of file subproblem.h.

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Member Function Documentation

cons SCIL::subproblem::add_basic_constraint (  cons_obj *    c, Activation    a = Dynamic )  [virtual]

adds an instance of a basic-constraint-schema to the root or the current node of the BCP-tree. Definition at line 32 of file core-abacus/subproblem.cc. References SCIL::cons_obj::Acons(), SCIL::cons_obj::init(), SCIL::ILP_Problem::nconss, and SCIL::ILP_Problem::number_of_constraints().

cons SCIL::subproblem::add_basic_constraint (  cons_sense   , double   , Activation    a = Dynamic )  [virtual]

adds a primitive basic constraint to the root or the current node of the BCP-tree (depends on the parameter |Validity|). |s| specifies the sense (one of |Less|, |Equal|, or |Greater|) and |r| the right-hand-side of the constraint.} Definition at line 43 of file core-abacus/subproblem.cc.

void subproblem::add_variable (  var   , Activation    a = Static )

adds a variable-generator to the root or the current node of the BCP-tree. Definition at line 89 of file core-abacus/subproblem.cc. References SCIL::var::Avar_pointer(), SCIL::var_obj::init(), SCIL::ILP_Problem::nvars, and SCIL::var::var_pointer().

var SCIL::subproblem::add_variable (  double    obj, double    lBound, double    uBound, Vartype   , Activation    a = Static )

adds a primitve variable to the root or the current node of the BCP-tree (depends on the parameter |Validity|). |obj| specifies the objectiv function value, |lBound| and |uBound| the lower and upper bound of the variable and |vt| the type of the variable (one of |Vartype_Integer| or |Vartype_Continous|).} Definition at line 53 of file core-abacus/subproblem.cc. References SCIL::var::Avar_pointer(), SCIL::var_obj::init(), SCIL::ILP_Problem::nvars, and SCIL::var::var_pointer().

void subproblem::remove_variable (  var    V )

removes a variable for the linear program of the current node. Definition at line 296 of file core-abacus/subproblem.cc. References SCIL::var_obj::index(), and SCIL::var::var_pointer().

void subproblem::set_coefficient (  var    v, cons    i, double    d )

sets the coefficient for variable $v$ and basic constraint $i$ to $d$ in the LP-Matrix. Definition at line 312 of file core-abacus/subproblem.cc. References SCIL::cons::cons_pointer(), SCIL::cons_obj::set(), SCIL::var_obj::set(), and SCIL::var::var_pointer().

double subproblem::value (  cons    i, as_what    as = as_is )

returns the value of |i| of the last solved LP. as_what is one of as_is, as_min or as_max. The returned dual value of the constraint is either the dual value as specified by the LP (as_is) or what it would be if the objective sense of the LP would be minimization (as_min) or maximization (as_max). Definition at line 387 of file core-abacus/subproblem.cc. References SCIL::cons_obj::Acons(), SCIL::cons::cons_pointer(), and SCIL::ILP_Problem::opt_sense().

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

• subproblem.h
• core-abacus/subproblem.cc
• core-scip/subproblem.cc

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