Detailed Description

functions for presolver plugins

Topics
	Special Methods
	methods commonly used for presolving

Functions
	SCIP_DECL_SORTPTRCOMP (SCIPpresolComp)
	SCIP_DECL_SORTPTRCOMP (SCIPpresolCompName)
SCIP_PRESOLDATA *	SCIPpresolGetData (SCIP_PRESOL *presol)
void	SCIPpresolSetData (SCIP_PRESOL presol, SCIP_PRESOLDATA presoldata)
void	SCIPpresolMarkExact (SCIP_PRESOL *presol)
const char *	SCIPpresolGetName (SCIP_PRESOL *presol)
const char *	SCIPpresolGetDesc (SCIP_PRESOL *presol)
int	SCIPpresolGetPriority (SCIP_PRESOL *presol)
int	SCIPpresolGetMaxrounds (SCIP_PRESOL *presol)
SCIP_PRESOLTIMING	SCIPpresolGetTiming (SCIP_PRESOL *presol)
void	SCIPpresolSetTiming (SCIP_PRESOL *presol, SCIP_PRESOLTIMING timing)
SCIP_Bool	SCIPpresolIsInitialized (SCIP_PRESOL *presol)
SCIP_Real	SCIPpresolGetSetupTime (SCIP_PRESOL *presol)
SCIP_Real	SCIPpresolGetTime (SCIP_PRESOL *presol)
int	SCIPpresolGetNFixedVars (SCIP_PRESOL *presol)
int	SCIPpresolGetNAggrVars (SCIP_PRESOL *presol)
int	SCIPpresolGetNChgVarTypes (SCIP_PRESOL *presol)
int	SCIPpresolGetNChgBds (SCIP_PRESOL *presol)
int	SCIPpresolGetNAddHoles (SCIP_PRESOL *presol)
int	SCIPpresolGetNDelConss (SCIP_PRESOL *presol)
int	SCIPpresolGetNAddConss (SCIP_PRESOL *presol)
int	SCIPpresolGetNUpgdConss (SCIP_PRESOL *presol)
int	SCIPpresolGetNChgCoefs (SCIP_PRESOL *presol)
int	SCIPpresolGetNChgSides (SCIP_PRESOL *presol)
int	SCIPpresolGetNCalls (SCIP_PRESOL *presol)
SCIP_RETCODE	SCIPincludePresol (SCIP scip, const char name, const char desc, int priority, int maxrounds, SCIP_PRESOLTIMING timing, SCIP_DECL_PRESOLCOPY((presolcopy)), SCIP_DECL_PRESOLFREE((presolfree)), SCIP_DECL_PRESOLINIT((presolinit)), SCIP_DECL_PRESOLEXIT((presolexit)), SCIP_DECL_PRESOLINITPRE((presolinitpre)), SCIP_DECL_PRESOLEXITPRE((presolexitpre)), SCIP_DECL_PRESOLEXEC((presolexec)), SCIP_PRESOLDATA *presoldata)
SCIP_RETCODE	SCIPincludePresolBasic (SCIP scip, SCIP_PRESOL presolptr, const char name, const char desc, int priority, int maxrounds, SCIP_PRESOLTIMING timing, SCIP_DECL_PRESOLEXEC((presolexec)), SCIP_PRESOLDATA *presoldata)
SCIP_RETCODE	SCIPsetPresolCopy (SCIP scip, SCIP_PRESOL presol,)
SCIP_RETCODE	SCIPsetPresolFree (SCIP scip, SCIP_PRESOL presol,)
SCIP_RETCODE	SCIPsetPresolInit (SCIP scip, SCIP_PRESOL presol,)
SCIP_RETCODE	SCIPsetPresolExit (SCIP scip, SCIP_PRESOL presol,)
SCIP_RETCODE	SCIPsetPresolInitpre (SCIP scip, SCIP_PRESOL presol,)
SCIP_RETCODE	SCIPsetPresolExitpre (SCIP scip, SCIP_PRESOL presol,)
SCIP_PRESOL *	SCIPfindPresol (SCIP scip, const char name)
SCIP_PRESOL **	SCIPgetPresols (SCIP *scip)
int	SCIPgetNPresols (SCIP *scip)
SCIP_RETCODE	SCIPsetPresolPriority (SCIP scip, SCIP_PRESOL presol, int priority)
int	SCIPgetNPresolRounds (SCIP *scip)

Function Documentation

◆ SCIP_DECL_SORTPTRCOMP() [1/2]

SCIP_DECL_SORTPTRCOMP ( SCIPpresolComp )

compares two presolvers w. r. to their priority

Definition at line 57 of file presol.c.

References SCIP_DECL_SORTPTRCOMP.

◆ SCIP_DECL_SORTPTRCOMP() [2/2]

SCIP_DECL_SORTPTRCOMP ( SCIPpresolCompName )

comparison method for sorting presolvers w.r.t. to their name

Definition at line 63 of file presol.c.

References SCIP_DECL_SORTPTRCOMP, and SCIPpresolGetName().

◆ SCIPpresolGetData()

SCIP_PRESOLDATA * SCIPpresolGetData ( SCIP_PRESOL * presol )

gets user data of presolver

Parameters

presol presolver

Definition at line 528 of file presol.c.

References assert(), NULL, SCIP_Presol::presoldata, and SCIPpresolGetData().

◆ SCIPpresolSetData()

void SCIPpresolSetData	(	SCIP_PRESOL *	presol,
		SCIP_PRESOLDATA *	presoldata )

sets user data of presolver; user has to free old data in advance!

Parameters

presol	presolver
presoldata	new presolver user data

Definition at line 538 of file presol.c.

References assert(), NULL, SCIP_Presol::presoldata, and SCIPpresolSetData().

Referenced by SCIP_DECL_PRESOLFREE(), SCIP_DECL_PRESOLFREE(), SCIP_DECL_PRESOLFREE(), SCIP_DECL_PRESOLFREE(), SCIP_DECL_PRESOLFREE(), SCIP_DECL_PRESOLFREE(), SCIP_DECL_PRESOLFREE(), SCIP_DECL_PRESOLFREE(), SCIP_DECL_PRESOLFREE(), SCIP_DECL_PRESOLFREE(), SCIP_DECL_PRESOLFREE(), SCIP_DECL_PRESOLFREE(), and SCIPpresolSetData().

◆ SCIPpresolMarkExact()

void SCIPpresolMarkExact ( SCIP_PRESOL * presol )

marks the presolver as safe to use in exact solving mode

Parameters

presol presolver

Definition at line 615 of file presol.c.

References assert(), SCIP_Presol::exact, NULL, SCIPpresolMarkExact(), and TRUE.

Referenced by SCIPpresolMarkExact().

◆ SCIPpresolGetName()

const char * SCIPpresolGetName ( SCIP_PRESOL * presol )

gets name of presolver

Parameters

presol presolver

Definition at line 625 of file presol.c.

References assert(), SCIP_Presol::name, NULL, and SCIPpresolGetName().

◆ SCIPpresolGetDesc()

const char * SCIPpresolGetDesc ( SCIP_PRESOL * presol )

gets description of presolver

Parameters

presol presolver

Definition at line 635 of file presol.c.

References assert(), SCIP_Presol::desc, NULL, and SCIPpresolGetDesc().

Referenced by SCIP_DECL_DIALOGEXEC(), SCIPcollectPresolverStatistics(), SCIPincludeDialogDefaultFix(), SCIPincludeDialogDefaultSet(), and SCIPpresolGetDesc().

◆ SCIPpresolGetPriority()

int SCIPpresolGetPriority ( SCIP_PRESOL * presol )

gets priority of presolver

Parameters

presol presolver

Definition at line 645 of file presol.c.

References assert(), NULL, SCIP_Presol::priority, and SCIPpresolGetPriority().

Referenced by presolveRound(), SCIP_DECL_DIALOGEXEC(), and SCIPpresolGetPriority().

◆ SCIPpresolGetMaxrounds()

int SCIPpresolGetMaxrounds ( SCIP_PRESOL * presol )

gets round limit of presolver

Parameters

presol presolver

Definition at line 655 of file presol.c.

References assert(), SCIP_Presol::maxrounds, NULL, and SCIPpresolGetMaxrounds().

Referenced by SCIP_DECL_DIALOGEXEC(), and SCIPpresolGetMaxrounds().

◆ SCIPpresolGetTiming()

SCIP_PRESOLTIMING SCIPpresolGetTiming ( SCIP_PRESOL * presol )

gets the timing mask of the presolver

Parameters

presol presolver

Definition at line 679 of file presol.c.

References assert(), NULL, SCIPpresolGetTiming(), and SCIP_Presol::timing.

Referenced by SCIP_DECL_DIALOGEXEC(), and SCIPpresolGetTiming().

◆ SCIPpresolSetTiming()

void SCIPpresolSetTiming	(	SCIP_PRESOL *	presol,
		SCIP_PRESOLTIMING	timing )

sets the timing mask of the presolver

Parameters

presol	presolver
timing	timing mask of the presolver

Definition at line 689 of file presol.c.

References assert(), NULL, SCIPpresolSetTiming(), and SCIP_Presol::timing.

Referenced by SCIPpresolSetTiming().

◆ SCIPpresolIsInitialized()

SCIP_Bool SCIPpresolIsInitialized ( SCIP_PRESOL * presol )

is presolver initialized?

Parameters

presol presolver

Definition at line 700 of file presol.c.

References assert(), SCIP_Presol::initialized, NULL, SCIP_Bool, and SCIPpresolIsInitialized().

Referenced by SCIPpresolIsInitialized().

◆ SCIPpresolGetSetupTime()

SCIP_Real SCIPpresolGetSetupTime ( SCIP_PRESOL * presol )

gets time in seconds used in this presolver for setting up for next stages

Parameters

presol presolver

Definition at line 722 of file presol.c.

References assert(), NULL, SCIP_Real, SCIPclockGetTime(), SCIPpresolGetSetupTime(), and SCIP_Presol::setuptime.

Referenced by SCIPcollectPresolverStatistics(), SCIPpresolGetSetupTime(), and SCIPprintPresolverStatistics().

◆ SCIPpresolGetTime()

SCIP_Real SCIPpresolGetTime ( SCIP_PRESOL * presol )

gets time in seconds used in this presolver

Parameters

presol presolver

Definition at line 732 of file presol.c.

References assert(), NULL, SCIP_Presol::presolclock, SCIP_Real, SCIPclockGetTime(), and SCIPpresolGetTime().

Referenced by SCIPcollectPresolverStatistics(), SCIPpresolGetTime(), and SCIPprintPresolverStatistics().

◆ SCIPpresolGetNFixedVars()

int SCIPpresolGetNFixedVars ( SCIP_PRESOL * presol )

gets number of variables fixed in presolver

Parameters

presol presolver

Definition at line 742 of file presol.c.

References assert(), SCIP_Presol::nfixedvars, NULL, and SCIPpresolGetNFixedVars().

Referenced by SCIPcollectPresolverStatistics(), SCIPpresolGetNFixedVars(), and SCIPprintPresolverStatistics().

◆ SCIPpresolGetNAggrVars()

int SCIPpresolGetNAggrVars ( SCIP_PRESOL * presol )

gets number of variables aggregated in presolver

Parameters

presol presolver

Definition at line 752 of file presol.c.

References assert(), SCIP_Presol::naggrvars, NULL, and SCIPpresolGetNAggrVars().

Referenced by SCIPcollectPresolverStatistics(), SCIPpresolGetNAggrVars(), and SCIPprintPresolverStatistics().

◆ SCIPpresolGetNChgVarTypes()

int SCIPpresolGetNChgVarTypes ( SCIP_PRESOL * presol )

gets number of variable types changed in presolver

Parameters

presol presolver

Definition at line 762 of file presol.c.

References assert(), SCIP_Presol::nchgvartypes, NULL, and SCIPpresolGetNChgVarTypes().

Referenced by SCIPcollectPresolverStatistics(), SCIPpresolGetNChgVarTypes(), and SCIPprintPresolverStatistics().

◆ SCIPpresolGetNChgBds()

int SCIPpresolGetNChgBds ( SCIP_PRESOL * presol )

gets number of bounds changed in presolver

Parameters

presol presolver

Definition at line 772 of file presol.c.

References assert(), SCIP_Presol::nchgbds, NULL, and SCIPpresolGetNChgBds().

Referenced by SCIPcollectPresolverStatistics(), SCIPpresolGetNChgBds(), and SCIPprintPresolverStatistics().

◆ SCIPpresolGetNAddHoles()

int SCIPpresolGetNAddHoles ( SCIP_PRESOL * presol )

gets number of holes added to domains of variables in presolver

Parameters

presol presolver

Definition at line 782 of file presol.c.

References assert(), SCIP_Presol::naddholes, NULL, and SCIPpresolGetNAddHoles().

Referenced by SCIPcollectPresolverStatistics(), SCIPpresolGetNAddHoles(), and SCIPprintPresolverStatistics().

◆ SCIPpresolGetNDelConss()

int SCIPpresolGetNDelConss ( SCIP_PRESOL * presol )

gets number of constraints deleted in presolver

Parameters

presol presolver

Definition at line 792 of file presol.c.

References assert(), SCIP_Presol::ndelconss, NULL, and SCIPpresolGetNDelConss().

Referenced by SCIPcollectPresolverStatistics(), SCIPpresolGetNDelConss(), and SCIPprintPresolverStatistics().

◆ SCIPpresolGetNAddConss()

int SCIPpresolGetNAddConss ( SCIP_PRESOL * presol )

gets number of constraints added in presolver

Parameters

presol presolver

Definition at line 802 of file presol.c.

References assert(), SCIP_Presol::naddconss, NULL, and SCIPpresolGetNAddConss().

Referenced by SCIPcollectPresolverStatistics(), SCIPpresolGetNAddConss(), and SCIPprintPresolverStatistics().

◆ SCIPpresolGetNUpgdConss()

int SCIPpresolGetNUpgdConss ( SCIP_PRESOL * presol )

gets number of constraints upgraded in presolver

Parameters

presol presolver

Definition at line 812 of file presol.c.

References assert(), NULL, SCIP_Presol::nupgdconss, and SCIPpresolGetNUpgdConss().

Referenced by SCIPpresolGetNUpgdConss().

◆ SCIPpresolGetNChgCoefs()

int SCIPpresolGetNChgCoefs ( SCIP_PRESOL * presol )

gets number of coefficients changed in presolver

Parameters

presol presolver

Definition at line 822 of file presol.c.

References assert(), SCIP_Presol::nchgcoefs, NULL, and SCIPpresolGetNChgCoefs().

Referenced by SCIP_DECL_PRESOLEXEC(), SCIPcollectPresolverStatistics(), SCIPpresolGetNChgCoefs(), and SCIPprintPresolverStatistics().

◆ SCIPpresolGetNChgSides()

int SCIPpresolGetNChgSides ( SCIP_PRESOL * presol )

gets number of constraint sides changed in presolver

Parameters

presol presolver

Definition at line 832 of file presol.c.

References assert(), SCIP_Presol::nchgsides, NULL, and SCIPpresolGetNChgSides().

Referenced by SCIPcollectPresolverStatistics(), SCIPpresolGetNChgSides(), and SCIPprintPresolverStatistics().

◆ SCIPpresolGetNCalls()

int SCIPpresolGetNCalls ( SCIP_PRESOL * presol )

gets number of times the presolver was called and tried to find reductions

Parameters

presol presolver

Definition at line 842 of file presol.c.

References assert(), SCIP_Presol::ncalls, NULL, and SCIPpresolGetNCalls().

Referenced by SCIPcollectPresolverStatistics(), SCIPpresolGetNCalls(), and SCIPprintPresolverStatistics().

◆ SCIPincludePresol()

SCIP_RETCODE SCIPincludePresol	(	SCIP *	scip,
		const char *	name,
		const char *	desc,
		int	priority,
		int	maxrounds,
		SCIP_PRESOLTIMING	timing,
		SCIP_DECL_PRESOLCOPY((*presolcopy))	,
		SCIP_DECL_PRESOLFREE((*presolfree))	,
		SCIP_DECL_PRESOLINIT((*presolinit))	,
		SCIP_DECL_PRESOLEXIT((*presolexit))	,
		SCIP_DECL_PRESOLINITPRE((*presolinitpre))	,
		SCIP_DECL_PRESOLEXITPRE((*presolexitpre))	,
		SCIP_DECL_PRESOLEXEC((*presolexec))	,
		SCIP_PRESOLDATA *	presoldata )

creates a presolver and includes it in SCIP

Note: method has all presolver callbacks as arguments and is thus changed every time a new callback is added in future releases; consider using SCIPincludePresolBasic() and setter functions if you seek for a method which is less likely to change in future releases

creates a presolver and includes it in SCIP.

Precondition

This method can be called if SCIP is in one of the following stages:

Note: method has all presolver callbacks as arguments and is thus changed every time a new callback is added in future releases; consider using SCIPincludePresolBasic() and setter functions if you seek for a method which is less likely to change in future releases

Parameters

scip	SCIP data structure
name	name of presolver
desc	description of presolver
priority	priority of the presolver (>= 0: before, < 0: after constraint handlers)
maxrounds	maximal number of presolving rounds the presolver participates in (-1: no limit)
timing	timing mask of the presolver
-	copy method of presolver or NULL if you don't want to copy your plugin into sub-SCIPs
-	destructor of presolver to free user data (called when SCIP is exiting)
-	initialization method of presolver (called after problem was transformed)
-	deinitialization method of presolver (called before transformed problem is freed)
-	presolving initialization method of presolver (called when presolving is about to begin)
-	presolving deinitialization method of presolver (called after presolving has been finished)
-	execution method of presolver
presoldata	presolver data

Definition at line 66 of file scip_presol.c.

References FALSE, NULL, SCIP_CALL, SCIP_DECL_PRESOLCOPY, SCIP_DECL_PRESOLEXEC, SCIP_DECL_PRESOLEXIT, SCIP_DECL_PRESOLEXITPRE, SCIP_DECL_PRESOLFREE, SCIP_DECL_PRESOLINIT, SCIP_DECL_PRESOLINITPRE, SCIP_INVALIDDATA, SCIP_OKAY, SCIPcheckStage, SCIPerrorMessage, SCIPfindPresol(), SCIPincludePresol(), SCIPpresolCreate(), SCIPsetIncludePresol(), and TRUE.

Referenced by SCIPincludeObjPresol(), and SCIPincludePresol().

◆ SCIPincludePresolBasic()

SCIP_RETCODE SCIPincludePresolBasic	(	SCIP *	scip,
		SCIP_PRESOL **	presolptr,
		const char *	name,
		const char *	desc,
		int	priority,
		int	maxrounds,
		SCIP_PRESOLTIMING	timing,
		SCIP_DECL_PRESOLEXEC((*presolexec))	,
		SCIP_PRESOLDATA *	presoldata )

Creates a presolver and includes it in SCIP with its fundamental callback. All non-fundamental (or optional) callbacks as, e.g., init and exit callbacks, will be set to NULL. Optional callbacks can be set via specific setter functions. These are SCIPsetPresolCopy(), SCIPsetPresolFree(), SCIPsetPresolInit(), SCIPsetPresolExit(), SCIPsetPresolInitpre(), and SCIPsetPresolExitPre().

Note: if you want to set all callbacks with a single method call, consider using SCIPincludePresol() instead

creates a presolver and includes it in SCIP with its fundamental callback. All non-fundamental (or optional) callbacks as, e.g., init and exit callbacks, will be set to NULL. Optional callbacks can be set via specific setter functions. These are SCIPsetPresolCopy(), SCIPsetPresolFree(), SCIPsetPresolInit(), SCIPsetPresolExit(), SCIPsetPresolInitpre(), and SCIPsetPresolExitPre().

Precondition

This method can be called if SCIP is in one of the following stages:

Note: if you want to set all callbacks with a single method call, consider using SCIPincludePresol() instead

Parameters

scip	SCIP data structure
presolptr	reference to presolver, or NULL
name	name of presolver
desc	description of presolver
priority	priority of the presolver (>= 0: before, < 0: after constraint handlers)
maxrounds	maximal number of presolving rounds the presolver participates in (-1: no limit)
timing	timing mask of the presolver
-	execution method of presolver
presoldata	presolver data