Scippy

SCIP

Solving Constraint Integer Programs

Detailed Description

Constraint handler for logicor constraints \(1^T x \ge 1\) (equivalent to set covering, but algorithms are suited for depth first search).

Author
Tobias Achterberg
Michael Winkler

Definition in file cons_logicor.h.

#include "scip/def.h"
#include "scip/type_cons.h"
#include "scip/type_lp.h"
#include "scip/type_retcode.h"
#include "scip/type_scip.h"
#include "scip/type_var.h"

Go to the source code of this file.

Functions

SCIP_EXPORT SCIP_RETCODE SCIPincludeConshdlrLogicor (SCIP *scip)
 
Logicor Constraints

This constraint handler handles a special type of linear constraints, namely logic or constraints. These are equivalent to set covering constraints, but are handled by special algorithms which are better suited for depth first search. For a set of binary variables \(x_i, i=1,\dots,n\), a logic or constraint has the form

\[ \sum_{i=1}^n x_i \ge 1. \]

SCIP_EXPORT SCIP_RETCODE SCIPcreateConsLogicor (SCIP *scip, SCIP_CONS **cons, const char *name, int nvars, SCIP_VAR **vars, SCIP_Bool initial, SCIP_Bool separate, SCIP_Bool enforce, SCIP_Bool check, SCIP_Bool propagate, SCIP_Bool local, SCIP_Bool modifiable, SCIP_Bool dynamic, SCIP_Bool removable, SCIP_Bool stickingatnode)
 
SCIP_EXPORT SCIP_RETCODE SCIPcreateConsBasicLogicor (SCIP *scip, SCIP_CONS **cons, const char *name, int nvars, SCIP_VAR **vars)
 
SCIP_EXPORT SCIP_RETCODE SCIPaddCoefLogicor (SCIP *scip, SCIP_CONS *cons, SCIP_VAR *var)
 
SCIP_EXPORT int SCIPgetNVarsLogicor (SCIP *scip, SCIP_CONS *cons)
 
SCIP_EXPORT SCIP_VAR ** SCIPgetVarsLogicor (SCIP *scip, SCIP_CONS *cons)
 
SCIP_EXPORT SCIP_Real SCIPgetDualsolLogicor (SCIP *scip, SCIP_CONS *cons)
 
SCIP_EXPORT SCIP_Real SCIPgetDualfarkasLogicor (SCIP *scip, SCIP_CONS *cons)
 
SCIP_EXPORT SCIP_ROWSCIPgetRowLogicor (SCIP *scip, SCIP_CONS *cons)
 
SCIP_EXPORT SCIP_RETCODE SCIPcleanupConssLogicor (SCIP *scip, SCIP_Bool onlychecked, int *naddconss, int *ndelconss, int *nchgcoefs)