Detailed Description

constraint handler for indicator constraints over arbitrary constraint types

Author: Ambros Gleixner; Frederic Pythoud

Superindicator constraints are constraints of the form

$x_i = 1 \Rightarrow C(x)$

where $ x_i $ is a binary variable and $C(\dot)$ a constraint. The superindicator constraint is satisfied if and only if x_i is zero or C is satisfied.

Definition in file cons_superindicator.h.

#include "scip/scip.h"

Go to the source code of this file.

Functions
SCIP_RETCODE	SCIPincludeConshdlrSuperindicator (SCIP *scip)

SCIP_RETCODE	SCIPcreateConsSuperindicator (SCIP scip, SCIP_CONS cons, const char name, SCIP_VAR binvar, SCIP_CONS slackcons, SCIP_Bool initial, SCIP_Bool separate, SCIP_Bool enforce, SCIP_Bool check, SCIP_Bool propagate, SCIP_Bool local, SCIP_Bool dynamic, SCIP_Bool removable, SCIP_Bool stickingatnode)

SCIP_RETCODE	SCIPcreateConsBasicSuperindicator (SCIP scip, SCIP_CONS cons, const char name, SCIP_VAR binvar, SCIP_CONS slackcons)

SCIP_VAR *	SCIPgetBinaryVarSuperindicator (SCIP_CONS *cons)

SCIP_CONS *	SCIPgetSlackConsSuperindicator (SCIP_CONS *cons)

SCIP_RETCODE	SCIPtransformMinUC (SCIP scip, SCIP_Bool success)

	SCIP_DECL_DIALOGEXEC (SCIPdialogExecChangeMinUC)

Function Documentation

SCIP_RETCODE SCIPincludeConshdlrSuperindicator ( SCIP * scip )

creates the handler for superindicator constraints and includes it in SCIP

Parameters

scip	SCIP data structure

SCIP_RETCODE SCIPcreateConsSuperindicator	(	SCIP *	scip,
		SCIP_CONS **	cons,
		const char *	name,
		SCIP_VAR *	binvar,
		SCIP_CONS *	slackcons,
		SCIP_Bool	initial,
		SCIP_Bool	separate,
		SCIP_Bool	enforce,
		SCIP_Bool	check,
		SCIP_Bool	propagate,
		SCIP_Bool	local,
		SCIP_Bool	dynamic,
		SCIP_Bool	removable,
		SCIP_Bool	stickingatnode
	)

creates and captures a superindicator constraint

Note: the constraint gets captured, hence at one point you have to release it using the method SCIPreleaseCons()

Parameters

scip	SCIP data structure
cons	pointer to hold the created constraint
name	name of constraint
binvar	pointer to the indicator constraint
slackcons	constraint corresponding to the handled constraint
initial	should the LP relaxation of constraint be in the initial LP? Usually set to TRUE. Set to FALSE for 'lazy constraints'.
separate	should the constraint be separated during LP processing? Usually set to TRUE.
enforce	should the constraint be enforced during node processing? TRUE for model constraints, FALSE for additional, redundant constraints.
check	should the constraint be checked for feasibility? TRUE for model constraints, FALSE for additional, redundant constraints.
propagate	should the constraint be propagated during node processing? Usually set to TRUE.
local	is constraint only valid locally? Usually set to FALSE. Has to be set to TRUE, e.g., for branching constraints.
dynamic	is constraint subject to aging? Usually set to FALSE. Set to TRUE for own cuts which are separated as constraints.
removable	should the relaxation be removed from the LP due to aging or cleanup? Usually set to FALSE. Set to TRUE for 'lazy constraints' and 'user cuts'.
stickingatnode	should the constraint always be kept at the node where it was added, even if it may be moved to a more global node? Usually set to FALSE. Set to TRUE to for constraints that represent node data.

SCIP_RETCODE SCIPcreateConsBasicSuperindicator	(	SCIP *	scip,
		SCIP_CONS **	cons,
		const char *	name,
		SCIP_VAR *	binvar,
		SCIP_CONS *	slackcons
	)

creates and captures a superindicator constraint in its most basic version, i. e., all constraint flags are set to their basic value as explained for the method SCIPcreateConsSuperindicator(); all flags can be set via SCIPsetConsFLAGNAME-methods in scip.h

See also: SCIPcreateConsSuperindicator() for information about the basic constraint flag configuration

Note: the constraint gets captured, hence at one point you have to release it using the method SCIPreleaseCons()

Parameters

scip	SCIP data structure
cons	pointer to hold the created constraint
name	name of constraint
binvar	pointer to the indicator constraint
slackcons	constraint corresponding to the handled constraint

SCIP_VAR* SCIPgetBinaryVarSuperindicator ( SCIP_CONS * cons )

gets binary variable corresponding to the superindicator constraint

Parameters

cons	superindicator constraint

SCIP_CONS* SCIPgetSlackConsSuperindicator ( SCIP_CONS * cons )

gets the slack constraint corresponding to the superindicator constraint

Parameters

cons	superindicator constraint

SCIP_RETCODE SCIPtransformMinUC	(	SCIP *	scip,
		SCIP_Bool *	success
	)

transforms the current problem into a MinUC problem (minimizing the number of unsatisfied constraints), a CIP generalization of the MinULR (min. unsatisfied linear relations) problem

Parameters

scip	SCIP data structure
success	pointer to store whether all constraints could be transformed

SCIP_DECL_DIALOGEXEC ( SCIPdialogExecChangeMinUC )

dialog execution method for the SCIPtransformMinUC() command

SCIP

Detailed Description

Functions

Function Documentation