Detailed Description

Constraint handler for variable bound constraints $lhs \le x + c y \le rhs$ .

Author: Tobias Achterberg; Timo Berthold; Michael Winkler; Gerald Gamrath; Stefan Heinz

This constraint handler handles a special type of linear constraints, namely variable bound constraints. A variable bound constraint has the form

$lhs \leq x + c y \leq rhs$

with coefficient $c \in Q$ , $lhs\in Q \cup \{-\infty\}$ , $rhs\in Q \cup \{\infty\}$ , and decision variables $x$ (non-binary) and $y$ (binary or integer).

Note: Although x must be non-binary when the constraint is created, it can happen that x is upgraded to a binary variable, e.g. due to aggregations or bound changes in presolving.

Definition in file cons_varbound.c.

#include <assert.h>
#include <string.h>
#include <limits.h>
#include <ctype.h>
#include "scip/cons_varbound.h"
#include "scip/cons_linear.h"
#include "scip/cons_setppc.h"

Go to the source code of this file.

Macros
Constraint handler properties
#define	CONSHDLR_NAME "varbound"

#define	CONSHDLR_DESC "variable bounds lhs <= x + c*y <= rhs, x non-binary, y non-continuous"

#define	CONSHDLR_SEPAPRIORITY +900000

#define	CONSHDLR_ENFOPRIORITY -500000

#define	CONSHDLR_CHECKPRIORITY -500000

#define	CONSHDLR_SEPAFREQ 0

#define	CONSHDLR_PROPFREQ 1

#define	CONSHDLR_EAGERFREQ 100

#define	CONSHDLR_MAXPREROUNDS -1

#define	CONSHDLR_DELAYSEPA FALSE

#define	CONSHDLR_DELAYPROP FALSE

#define	CONSHDLR_DELAYPRESOL FALSE

#define	CONSHDLR_NEEDSCONS TRUE

#define	CONSHDLR_PROP_TIMING SCIP_PROPTIMING_BEFORELP

#define	EVENTHDLR_NAME "varbound"

#define	EVENTHDLR_DESC "bound change event handler for variable bound constraints"

#define	LINCONSUPGD_PRIORITY +50000

Default parameter values
#define	DEFAULT_PRESOLPAIRWISE TRUE

#define	DEFAULT_MAXLPCOEF 1e+09

#define	DEFAULT_USEBDWIDENING TRUE

#define	MAXSCALEDCOEF 1000LL

Typedefs
typedef enum Proprule	PROPRULE

Enumerations
enum	Proprule { PROPRULE_1, PROPRULE_2, PROPRULE_3, PROPRULE_4, PROPRULE_INVALID, PROPRULE_INVALID = 0, PROPRULE_1 = 1, PROPRULE_2 = 2, PROPRULE_3 = 3, PROPRULE_4 = 4, PROPRULE_1_CORETIMES = 1, PROPRULE_2_EDGEFINDING = 2, PROPRULE_3_TTEF = 3, PROPRULE_1_RHS = 1, PROPRULE_1_LHS = 2, PROPRULE_INVALID = 0, PROPRULE_1, PROPRULE_2, PROPRULE_3, PROPRULE_4, PROPRULE_INVALID, PROPRULE_1, PROPRULE_2, PROPRULE_3, PROPRULE_4, PROPRULE_0, PROPRULE_1, PROPRULE_INTLB, PROPRULE_INTUB, PROPRULE_INVALID }

Functions
Local methods
static	SCIP_DECL_SORTPTRCOMP (consVarboundComp)

static SCIP_RETCODE	conshdlrdataCreate (SCIP scip, SCIP_CONSHDLRDATA conshdlrdata, SCIP_EVENTHDLR eventhdlr)

static void	conshdlrdataFree (SCIP scip, SCIP_CONSHDLRDATA *conshdlrdata)

static SCIP_RETCODE	catchEvents (SCIP scip, SCIP_CONS cons, SCIP_EVENTHDLR *eventhdlr)

static SCIP_RETCODE	dropEvents (SCIP scip, SCIP_CONS cons, SCIP_EVENTHDLR *eventhdlr)

static SCIP_RETCODE	consdataCreate (SCIP scip, SCIP_CONSDATA consdata, SCIP_VAR var, SCIP_VAR *vbdvar, SCIP_Real vbdcoef, SCIP_Real lhs, SCIP_Real rhs)

static SCIP_RETCODE	consdataFree (SCIP scip, SCIP_CONSDATA *consdata)

static SCIP_RETCODE	createRelaxation (SCIP scip, SCIP_CONS cons)

static SCIP_RETCODE	addRelaxation (SCIP scip, SCIP_CONS cons)

static SCIP_Bool	checkCons (SCIP scip, SCIP_CONS cons, SCIP_SOL *sol, SCIP_Bool checklprows)

static SCIP_RETCODE	resolvePropagation (SCIP scip, SCIP_CONS cons, SCIP_VAR infervar, PROPRULE proprule, SCIP_BOUNDTYPE boundtype, SCIP_BDCHGIDX bdchgidx, SCIP_Real inferbd, SCIP_Bool usebdwidening)

static SCIP_RETCODE	analyzeConflict (SCIP scip, SCIP_CONS cons, SCIP_VAR *infervar, SCIP_Real inferbd, PROPRULE proprule, SCIP_BOUNDTYPE boundtype, SCIP_Bool usebdwidening)

static SCIP_RETCODE	separateCons (SCIP scip, SCIP_CONS cons, SCIP_Bool usebdwidening, SCIP_SOL sol, SCIP_RESULT result)

static SCIP_RETCODE	chgLhs (SCIP scip, SCIP_CONS cons, SCIP_Real lhs)

static SCIP_RETCODE	chgRhs (SCIP scip, SCIP_CONS cons, SCIP_Real rhs)

static SCIP_RETCODE	propagateCons (SCIP scip, SCIP_CONS cons, SCIP_Bool usebdwidening, SCIP_Bool cutoff, int nchgbds, int nchgsides, int ndelconss)

static void	checkRedundancySide (SCIP scip, SCIP_VAR var, SCIP_VAR vbdvar, SCIP_Real coef0, SCIP_Real coef1, SCIP_Real side0, SCIP_Real side1, SCIP_Bool sideequal, SCIP_Bool cons0sidered, SCIP_Bool cons1sidered, SCIP_Bool islhs)

static SCIP_RETCODE	preprocessConstraintPairs (SCIP scip, SCIP_CONS conss, int nconss, SCIP_Bool cutoff, int nchgbds, int ndelconss, int nchgcoefs, int nchgsides)

static SCIP_RETCODE	prettifyConss (SCIP scip, SCIP_CONS conss, int nconss, int nchgcoefs, int *nchgsides)

static SCIP_RETCODE	applyFixings (SCIP scip, SCIP_CONS cons, SCIP_EVENTHDLR eventhdlr, SCIP_Bool cutoff, int nchgbds, int ndelconss, int *naddconss)

static SCIP_RETCODE	tightenCoefs (SCIP scip, SCIP_CONS cons, int nchgcoefs, int nchgsides, int *ndelconss)

static SCIP_RETCODE	upgradeConss (SCIP scip, SCIP_CONSHDLRDATA conshdlrdata, SCIP_CONS *conss, int nconss, SCIP_Bool cutoff, int naggrvars, int nchgbds, int nchgcoefs, int nchgsides, int ndelconss, int naddconss)

Linear constraint upgrading
static	SCIP_DECL_LINCONSUPGD (linconsUpgdVarbound)

Callback methods
static	SCIP_DECL_CONSHDLRCOPY (conshdlrCopyVarbound)

static	SCIP_DECL_CONSFREE (consFreeVarbound)

static	SCIP_DECL_CONSEXITSOL (consExitsolVarbound)

static	SCIP_DECL_CONSDELETE (consDeleteVarbound)

static	SCIP_DECL_CONSTRANS (consTransVarbound)

static	SCIP_DECL_CONSINITLP (consInitlpVarbound)

static	SCIP_DECL_CONSSEPALP (consSepalpVarbound)

static	SCIP_DECL_CONSSEPASOL (consSepasolVarbound)

static	SCIP_DECL_CONSENFOLP (consEnfolpVarbound)

static	SCIP_DECL_CONSENFOPS (consEnfopsVarbound)

static	SCIP_DECL_CONSCHECK (consCheckVarbound)

static	SCIP_DECL_CONSPROP (consPropVarbound)

static	SCIP_DECL_CONSPRESOL (consPresolVarbound)

static	SCIP_DECL_CONSRESPROP (consRespropVarbound)

static	SCIP_DECL_CONSLOCK (consLockVarbound)

static	SCIP_DECL_CONSPRINT (consPrintVarbound)

static	SCIP_DECL_CONSCOPY (consCopyVarbound)

static	SCIP_DECL_CONSPARSE (consParseVarbound)

static	SCIP_DECL_CONSGETVARS (consGetVarsVarbound)

static	SCIP_DECL_CONSGETNVARS (consGetNVarsVarbound)

static	SCIP_DECL_EVENTEXEC (eventExecVarbound)

Interface methods
SCIP_RETCODE	SCIPincludeConshdlrVarbound (SCIP *scip)

SCIP_RETCODE	SCIPcreateConsVarbound (SCIP scip, SCIP_CONS cons, const char name, SCIP_VAR var, SCIP_VAR vbdvar, SCIP_Real vbdcoef, SCIP_Real lhs, SCIP_Real rhs, 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_RETCODE	SCIPcreateConsBasicVarbound (SCIP scip, SCIP_CONS cons, const char name, SCIP_VAR var, SCIP_VAR vbdvar, SCIP_Real vbdcoef, SCIP_Real lhs, SCIP_Real rhs)

SCIP_Real	SCIPgetLhsVarbound (SCIP scip, SCIP_CONS cons)

SCIP_Real	SCIPgetRhsVarbound (SCIP scip, SCIP_CONS cons)

SCIP_VAR *	SCIPgetVarVarbound (SCIP scip, SCIP_CONS cons)

SCIP_VAR *	SCIPgetVbdvarVarbound (SCIP scip, SCIP_CONS cons)

SCIP_Real	SCIPgetVbdcoefVarbound (SCIP scip, SCIP_CONS cons)

SCIP_Real	SCIPgetDualsolVarbound (SCIP scip, SCIP_CONS cons)

SCIP_Real	SCIPgetDualfarkasVarbound (SCIP scip, SCIP_CONS cons)

SCIP_ROW *	SCIPgetRowVarbound (SCIP scip, SCIP_CONS cons)

Macro Definition Documentation

#define CONSHDLR_NAME "varbound"

Definition at line 53 of file cons_varbound.c.

Referenced by addRelaxation(), SCIP_DECL_CONSFREE(), SCIP_DECL_CONSHDLRCOPY(), SCIP_DECL_CONSPRESOL(), SCIPcreateConsVarbound(), SCIPgetDualfarkasVarbound(), SCIPgetDualsolVarbound(), SCIPgetLhsVarbound(), SCIPgetRhsVarbound(), SCIPgetRowVarbound(), SCIPgetVarVarbound(), SCIPgetVbdcoefVarbound(), SCIPgetVbdvarVarbound(), SCIPincludeConshdlrVarbound(), and separateCons().

#define CONSHDLR_DESC "variable bounds lhs <= x + c*y <= rhs, x non-binary, y non-continuous"

Definition at line 54 of file cons_varbound.c.

Referenced by SCIPincludeConshdlrVarbound().

#define CONSHDLR_SEPAPRIORITY +900000

priority of the constraint handler for separation

Definition at line 55 of file cons_varbound.c.

Referenced by SCIPincludeConshdlrVarbound().

#define CONSHDLR_ENFOPRIORITY -500000

priority of the constraint handler for constraint enforcing

Definition at line 56 of file cons_varbound.c.

Referenced by SCIPincludeConshdlrVarbound().

#define CONSHDLR_CHECKPRIORITY -500000

priority of the constraint handler for checking feasibility

Definition at line 57 of file cons_varbound.c.

Referenced by SCIPincludeConshdlrVarbound().

#define CONSHDLR_SEPAFREQ 0

frequency for separating cuts; zero means to separate only in the root node

Definition at line 58 of file cons_varbound.c.

Referenced by SCIPincludeConshdlrVarbound().

#define CONSHDLR_PROPFREQ 1

frequency for propagating domains; zero means only preprocessing propagation

Definition at line 59 of file cons_varbound.c.

Referenced by SCIPincludeConshdlrVarbound().

#define CONSHDLR_EAGERFREQ 100

frequency for using all instead of only the useful constraints in separation, propagation and enforcement, -1 for no eager evaluations, 0 for first only

Definition at line 60 of file cons_varbound.c.

Referenced by SCIPincludeConshdlrVarbound().

#define CONSHDLR_MAXPREROUNDS -1

maximal number of presolving rounds the constraint handler participates in (-1: no limit)

Definition at line 62 of file cons_varbound.c.

Referenced by SCIPincludeConshdlrVarbound().

#define CONSHDLR_DELAYSEPA FALSE

should separation method be delayed, if other separators found cuts?

Definition at line 63 of file cons_varbound.c.

Referenced by SCIPincludeConshdlrVarbound().

#define CONSHDLR_DELAYPROP FALSE

should propagation method be delayed, if other propagators found reductions?

Definition at line 64 of file cons_varbound.c.

Referenced by SCIPincludeConshdlrVarbound().

#define CONSHDLR_DELAYPRESOL FALSE

should presolving method be delayed, if other presolvers found reductions?

Definition at line 65 of file cons_varbound.c.

Referenced by SCIPincludeConshdlrVarbound().

#define CONSHDLR_NEEDSCONS TRUE

should the constraint handler be skipped, if no constraints are available?

Definition at line 66 of file cons_varbound.c.

Referenced by SCIPincludeConshdlrVarbound().

#define CONSHDLR_PROP_TIMING SCIP_PROPTIMING_BEFORELP

Definition at line 68 of file cons_varbound.c.

Referenced by SCIPincludeConshdlrVarbound().

#define EVENTHDLR_NAME "varbound"

Definition at line 70 of file cons_varbound.c.

Referenced by SCIPincludeConshdlrVarbound().

#define EVENTHDLR_DESC "bound change event handler for variable bound constraints"

Definition at line 71 of file cons_varbound.c.

Referenced by SCIPincludeConshdlrVarbound().

#define LINCONSUPGD_PRIORITY +50000

priority of the constraint handler for upgrading of linear constraints

Definition at line 73 of file cons_varbound.c.

Referenced by SCIPincludeConshdlrVarbound().

#define DEFAULT_PRESOLPAIRWISE TRUE

should pairwise constraint comparison be performed in presolving?

Definition at line 82 of file cons_varbound.c.

Referenced by SCIPincludeConshdlrVarbound().

#define DEFAULT_MAXLPCOEF 1e+09

maximum coefficient in varbound constraint to be added as a row into LP

Definition at line 83 of file cons_varbound.c.

Referenced by SCIPincludeConshdlrVarbound().

#define DEFAULT_USEBDWIDENING TRUE

should bound widening be used to initialize conflict analysis?

Definition at line 84 of file cons_varbound.c.

Referenced by SCIPincludeConshdlrVarbound().

#define MAXSCALEDCOEF 1000LL

maximal coefficient value after scaling

Definition at line 87 of file cons_varbound.c.

Referenced by prettifyConss().

Typedef Documentation

typedef enum Proprule PROPRULE

Definition at line 124 of file cons_varbound.c.

Enumeration Type Documentation

enum Proprule

Propagation rules

Enumerator:

PROPRULE_1	left hand side and bounds on z -> lower bound on x
PROPRULE_2	left hand side and upper bound on x -> bound on z
PROPRULE_3	right hand side and bounds on z -> upper bound on x
PROPRULE_4	right hand side and lower bound on x -> bound on z
PROPRULE_INVALID	propagation was applied without a specific propagation rule
PROPRULE_INVALID	propagation was applied without a specific propagation rule
PROPRULE_1	v_i = FALSE => r = FALSE
PROPRULE_2	r = TRUE => v_i = TRUE for all i
PROPRULE_3	v_i = TRUE for all i => r = TRUE
PROPRULE_4	r = FALSE, v_i = TRUE for all i except j => v_j = FALSE
PROPRULE_1_CORETIMES	core-time propagator
PROPRULE_2_EDGEFINDING	edge-finder
PROPRULE_3_TTEF	time-table edeg-finding
PROPRULE_1_RHS	activity residuals of all other variables tighten bounds of single variable due to the right hand side of the inequality
PROPRULE_1_LHS	activity residuals of all other variables tighten bounds of single variable due to the left hand side of the inequality
PROPRULE_INVALID	propagation was applied without a specific propagation rule
PROPRULE_1	v_i = TRUE => r = TRUE
PROPRULE_2	r = FALSE => v_i = FALSE for all i
PROPRULE_3	v_i = FALSE for all i => r = FALSE
PROPRULE_4	r = TRUE, v_i = FALSE for all i except j => v_j = TRUE
PROPRULE_INVALID	propagation was applied without a specific propagation rule
PROPRULE_1	left hand side and bounds on y -> lower bound on x
PROPRULE_2	left hand side and upper bound on x -> bound on y
PROPRULE_3	right hand side and bounds on y -> upper bound on x
PROPRULE_4	right hand side and lower bound on x -> bound on y
PROPRULE_0	all variables are fixed => fix integral variable
PROPRULE_1	all except one variable fixed => fix remaining variable
PROPRULE_INTLB	lower bound propagation of integral variable
PROPRULE_INTUB	upper bound propagation of integral variable
PROPRULE_INVALID	propagation was applied without a specific propagation rule

Definition at line 117 of file cons_varbound.c.

Function Documentation

static SCIP_DECL_SORTPTRCOMP ( consVarboundComp )

static

compares two varbound constraints cons1: $lhs1 \le x1 + c1 y1 \le rhs1$ and cons2: $lhs2 \le x2 + c2 y2 \le rhs2$ w.r.t. the indices of the contained variables

returns -1 if:

the index of x1 is smaller than the index of x2 or
x1 = x2 and the index of y1 is smaller than the index of y2 or
x1 = x2 and y1 = y2 and cons2 was recently changed, but cons1 not

returns 0 if x1 = x2, y1 = y2, and the changed status of both constraints is the same

and returns +1 otherwise

Definition at line 144 of file cons_varbound.c.

References NULL, SCIPconsGetData(), and SCIPvarGetIndex().

static SCIP_RETCODE conshdlrdataCreate	(	SCIP *	scip,
		SCIP_CONSHDLRDATA **	conshdlrdata,
		SCIP_EVENTHDLR *	eventhdlr
	)

static

creates constraint handler data for varbound constraint handler

Parameters

scip	SCIP data structure
conshdlrdata	pointer to store the constraint handler data
eventhdlr	event handler

Definition at line 180 of file cons_varbound.c.

References NULL, SCIP_CALL, SCIP_OKAY, and SCIPallocMemory.

Referenced by SCIPincludeConshdlrVarbound().

static void conshdlrdataFree	(	SCIP *	scip,
		SCIP_CONSHDLRDATA **	conshdlrdata
	)

static

frees constraint handler data for varbound constraint handler

Parameters

scip	SCIP data structure
conshdlrdata	pointer to the constraint handler data

Definition at line 199 of file cons_varbound.c.

References NULL, and SCIPfreeMemory.

Referenced by SCIP_DECL_CONSFREE().

static SCIP_RETCODE catchEvents	(	SCIP *	scip,
		SCIP_CONS *	cons,
		SCIP_EVENTHDLR *	eventhdlr
	)

static

catches events for variables

Parameters

scip	SCIP data structure
cons	variable bound constraint
eventhdlr	event handler

Definition at line 216 of file cons_varbound.c.

References NULL, SCIP_CALL, SCIP_EVENTTYPE_BOUNDTIGHTENED, SCIP_EVENTTYPE_VARFIXED, SCIP_OKAY, SCIPcatchVarEvent(), and SCIPconsGetData().

Referenced by applyFixings(), SCIP_DECL_CONSTRANS(), and SCIPcreateConsVarbound().

static SCIP_RETCODE dropEvents	(	SCIP *	scip,
		SCIP_CONS *	cons,
		SCIP_EVENTHDLR *	eventhdlr
	)

static

drops events for variables

Parameters

scip	SCIP data structure
cons	variable bound constraint
eventhdlr	event handler

Definition at line 236 of file cons_varbound.c.

References NULL, SCIP_CALL, SCIP_EVENTTYPE_BOUNDTIGHTENED, SCIP_EVENTTYPE_VARFIXED, SCIP_OKAY, SCIPconsGetData(), and SCIPdropVarEvent().

Referenced by applyFixings(), and SCIP_DECL_CONSDELETE().

static SCIP_RETCODE consdataCreate	(	SCIP *	scip,
		SCIP_CONSDATA **	consdata,
		SCIP_VAR *	var,
		SCIP_VAR *	vbdvar,
		SCIP_Real	vbdcoef,
		SCIP_Real	lhs,
		SCIP_Real	rhs
	)

static

creates a variable bound constraint data object

Parameters

scip	SCIP data structure
consdata	pointer to store the variable bound constraint data
var	variable x that has variable bound
vbdvar	binary, integer or implicit integer bounding variable y
vbdcoef	coefficient c of bounding variable y
lhs	left hand side of variable bound inequality
rhs	right hand side of variable bound inequality

Definition at line 256 of file cons_varbound.c.

References FALSE, NULL, SCIP_CALL, SCIP_INVALIDDATA, SCIP_OKAY, SCIP_VARSTATUS_MULTAGGR, SCIP_VARTYPE_CONTINUOUS, SCIPallocBlockMemory, SCIPcaptureVar(), SCIPerrorMessage, SCIPgetTransformedVar(), SCIPinfinity(), SCIPisGT(), SCIPisInfinity(), SCIPisTransformed(), SCIPvarGetProbvar(), SCIPvarGetStatus(), SCIPvarGetType(), and TRUE.

Referenced by SCIP_DECL_CONSTRANS(), and SCIPcreateConsVarbound().

static SCIP_RETCODE consdataFree	(	SCIP *	scip,
		SCIP_CONSDATA **	consdata
	)

static

frees a variable bound constraint data

Parameters

scip	SCIP data structure
consdata	pointer to the variable bound constraint

Definition at line 326 of file cons_varbound.c.

References NULL, SCIP_CALL, SCIP_OKAY, SCIPfreeBlockMemory, SCIPreleaseRow(), and SCIPreleaseVar().

Referenced by SCIP_DECL_CONSDELETE().

static SCIP_RETCODE createRelaxation	(	SCIP *	scip,
		SCIP_CONS *	cons
	)

static

creates LP row corresponding to variable bound constraint

Parameters

scip	SCIP data structure
cons	variable bound constraint

Definition at line 351 of file cons_varbound.c.

References NULL, SCIP_CALL, SCIP_OKAY, SCIPaddVarToRow(), SCIPconsGetData(), SCIPconsGetHdlr(), SCIPconsGetName(), SCIPconsIsLocal(), SCIPconsIsModifiable(), SCIPconsIsRemovable(), and SCIPcreateEmptyRowCons().

Referenced by addRelaxation(), and separateCons().

static SCIP_RETCODE addRelaxation	(	SCIP *	scip,
		SCIP_CONS *	cons
	)

static

adds linear relaxation of variable bound constraint to the LP

Parameters

scip	SCIP data structure
cons	variable bound constraint

Definition at line 372 of file cons_varbound.c.

References CONSHDLR_NAME, createRelaxation(), FALSE, NULL, REALABS, SCIP_Bool, SCIP_CALL, SCIP_OKAY, SCIP_PLUGINNOTFOUND, SCIP_VARTYPE_CONTINUOUS, SCIPaddCut(), SCIPconsGetData(), SCIPconsGetName(), SCIPconshdlrGetData(), SCIPdebug, SCIPdebugMessage, SCIPerrorMessage, SCIPfindConshdlr(), SCIPisGT(), SCIPprintRow(), SCIProwIsInLP(), and SCIPvarGetType().

Referenced by SCIP_DECL_CONSINITLP().

static SCIP_Bool checkCons	(	SCIP *	scip,
		SCIP_CONS *	cons,
		SCIP_SOL *	sol,
		SCIP_Bool	checklprows
	)

static

returns whether the given solution is feasible for the given variable bound constraint

Parameters

scip	SCIP data structure
cons	variable bound constraint
sol	solution to check, NULL for current solution
checklprows	should LP rows be checked?

Definition at line 422 of file cons_varbound.c.

References FALSE, NULL, SCIP_Real, SCIPconsGetData(), SCIPconsGetName(), SCIPdebugMessage, SCIPgetSolVal(), SCIPisFeasGE(), SCIPisFeasLE(), SCIPisFeasZero(), SCIPisInfinity(), SCIProwIsInLP(), and TRUE.

Referenced by SCIP_DECL_CONSCHECK(), SCIP_DECL_CONSENFOLP(), SCIP_DECL_CONSENFOPS(), and separateCons().

static SCIP_RETCODE resolvePropagation	(	SCIP *	scip,
		SCIP_CONS *	cons,
		SCIP_VAR *	infervar,
		PROPRULE	proprule,
		SCIP_BOUNDTYPE	boundtype,
		SCIP_BDCHGIDX *	bdchgidx,
		SCIP_Real	inferbd,
		SCIP_Bool	usebdwidening
	)

static

resolves a propagation on the given variable by supplying the variables needed for applying the corresponding propagation rule (see propagateCons()): (1) left hand side and bounds on y -> lower bound on x (2) left hand side and upper bound on x -> bound on y (3) right hand side and bounds on y -> upper bound on x (4) right hand side and lower bound on x -> bound on y

Parameters

scip	SCIP data structure
cons	constraint that inferred the bound change
infervar	variable that was deduced
proprule	propagation rule that deduced the bound change
boundtype	the type of the changed bound (lower or upper bound)
bdchgidx	bound change index (time stamp of bound change), or NULL for current time
inferbd	inference bound which needs to be explained
usebdwidening	should bound widening be used to in conflict analysis?

Definition at line 466 of file cons_varbound.c.

References NULL, PROPRULE_1, PROPRULE_2, PROPRULE_3, PROPRULE_4, SCIP_BOUNDTYPE_LOWER, SCIP_BOUNDTYPE_UPPER, SCIP_CALL, SCIP_INVALIDDATA, SCIP_OKAY, SCIP_Real, SCIP_VARTYPE_CONTINUOUS, SCIPaddConflictLb(), SCIPaddConflictRelaxedLb(), SCIPaddConflictRelaxedUb(), SCIPaddConflictUb(), SCIPadjustedVarLb(), SCIPadjustedVarUb(), SCIPconsGetData(), SCIPconsGetName(), SCIPerrorMessage, SCIPfeastol(), SCIPisEQ(), SCIPisInfinity(), SCIPisZero(), SCIPvarGetType(), and SCIPvarIsIntegral().

Referenced by analyzeConflict(), and SCIP_DECL_CONSRESPROP().

static SCIP_RETCODE analyzeConflict	(	SCIP *	scip,
		SCIP_CONS *	cons,
		SCIP_VAR *	infervar,
		SCIP_Real	inferbd,
		PROPRULE	proprule,
		SCIP_BOUNDTYPE	boundtype,
		SCIP_Bool	usebdwidening
	)

static

analyze infeasibility

Parameters

scip	SCIP data structure
cons	variable bound constraint
infervar	variable that was deduced
inferbd	bound which led to infeasibility
proprule	propagation rule that deduced the bound change
boundtype	the type of the changed bound (lower or upper bound)
usebdwidening	should bound widening be used to in conflict analysis?

Definition at line 673 of file cons_varbound.c.

References MAX, NULL, REALABS, resolvePropagation(), SCIP_BOUNDTYPE_LOWER, SCIP_BOUNDTYPE_UPPER, SCIP_CALL, SCIP_OKAY, SCIP_Real, SCIP_STAGE_SOLVING, SCIPaddConflictLb(), SCIPaddConflictRelaxedLb(), SCIPaddConflictRelaxedUb(), SCIPaddConflictUb(), SCIPadjustedVarLb(), SCIPadjustedVarUb(), SCIPanalyzeConflictCons(), SCIPconsGetData(), SCIPfeastol(), SCIPgetConflictVarLb(), SCIPgetConflictVarUb(), SCIPgetStage(), SCIPinitConflictAnalysis(), SCIPinProbing(), SCIPisConflictAnalysisApplicable(), and SCIPvarIsIntegral().

Referenced by propagateCons(), and separateCons().

static SCIP_RETCODE separateCons	(	SCIP *	scip,
		SCIP_CONS *	cons,
		SCIP_Bool	usebdwidening,
		SCIP_SOL *	sol,
		SCIP_RESULT *	result
	)

static

separates the given variable bound constraint

Parameters

scip	SCIP data structure
cons	variable bound constraint
usebdwidening	should bound widening be used to in conflict analysis?
sol	primal CIP solution, NULL for current LP solution
result	pointer to store the result of the separation call

Definition at line 839 of file cons_varbound.c.

References analyzeConflict(), checkCons(), CONSHDLR_NAME, createRelaxation(), FALSE, NULL, PROPRULE_1, PROPRULE_3, SCIP_Bool, SCIP_BOUNDTYPE_LOWER, SCIP_BOUNDTYPE_UPPER, SCIP_CALL, SCIP_CUTOFF, SCIP_OKAY, SCIP_PLUGINNOTFOUND, SCIP_Real, SCIP_REDUCEDDOM, SCIP_SEPARATED, SCIP_VARTYPE_CONTINUOUS, SCIPaddCut(), SCIPconsGetData(), SCIPconsGetName(), SCIPdebugMessage, SCIPerrorMessage, SCIPfindConshdlr(), SCIPgetRowSolFeasibility(), SCIPinferVarLbCons(), SCIPinferVarUbCons(), SCIPisFeasEQ(), SCIPisFeasNegative(), SCIPisGT(), SCIPisInfinity(), SCIPisLT(), SCIProwIsInLP(), SCIPvarGetLbLocal(), SCIPvarGetType(), SCIPvarGetUbLocal(), and TRUE.

Referenced by SCIP_DECL_CONSENFOLP(), SCIP_DECL_CONSSEPALP(), and SCIP_DECL_CONSSEPASOL().

static SCIP_RETCODE chgLhs	(	SCIP *	scip,
		SCIP_CONS *	cons,
		SCIP_Real	lhs
	)

static

sets left hand side of varbound constraint

Parameters

scip	SCIP data structure
cons	linear constraint
lhs	new left hand side

Definition at line 970 of file cons_varbound.c.

References FALSE, NULL, SCIP_CALL, SCIP_OKAY, SCIPconsGetData(), SCIPconsIsLocked(), SCIPconsIsTransformed(), SCIPinfinity(), SCIPisEQ(), SCIPisInfinity(), SCIPisLT(), SCIPisPositive(), SCIPlockVarCons(), SCIPunlockVarCons(), and TRUE.

Referenced by preprocessConstraintPairs(), and propagateCons().

static SCIP_RETCODE chgRhs	(	SCIP *	scip,
		SCIP_CONS *	cons,
		SCIP_Real	rhs
	)

static

sets right hand side of varbound constraint

Parameters

scip	SCIP data structure
cons	linear constraint
rhs	new right hand side

Definition at line 1052 of file cons_varbound.c.

References FALSE, NULL, SCIP_CALL, SCIP_OKAY, SCIPconsGetData(), SCIPconsIsLocked(), SCIPconsIsTransformed(), SCIPinfinity(), SCIPisEQ(), SCIPisGT(), SCIPisInfinity(), SCIPisPositive(), SCIPlockVarCons(), SCIPunlockVarCons(), and TRUE.

Referenced by preprocessConstraintPairs(), and propagateCons().

static SCIP_RETCODE propagateCons	(	SCIP *	scip,
		SCIP_CONS *	cons,
		SCIP_Bool	usebdwidening,
		SCIP_Bool *	cutoff,
		int *	nchgbds,
		int *	nchgsides,
		int *	ndelconss
	)

static

propagation method for variable bound constraint

Parameters

scip	SCIP data structure
cons	variable bound constraint
usebdwidening	should bound widening be used to in conflict analysis?
cutoff	pointer to store whether the node can be cut off
nchgbds	pointer to count number of bound changes
nchgsides	pointer to count number of side changes
ndelconss	pointer to count number of deleted constraints, or NULL

Definition at line 1134 of file cons_varbound.c.

References analyzeConflict(), chgLhs(), chgRhs(), FALSE, NULL, PROPRULE_1, PROPRULE_2, PROPRULE_3, PROPRULE_4, SCIP_Bool, SCIP_BOUNDTYPE_LOWER, SCIP_BOUNDTYPE_UPPER, SCIP_CALL, SCIP_OKAY, SCIP_Real, SCIP_STAGE_PRESOLVING, SCIP_VARSTATUS_MULTAGGR, SCIPadjustedVarLb(), SCIPadjustedVarUb(), SCIPconsGetData(), SCIPconsGetName(), SCIPdebugMessage, SCIPdelConsLocal(), SCIPgetStage(), SCIPincConsAge(), SCIPinferVarLbCons(), SCIPinferVarUbCons(), SCIPinfinity(), SCIPinProbing(), SCIPinRepropagation(), SCIPisFeasGE(), SCIPisFeasLE(), SCIPisGT(), SCIPisInfinity(), SCIPisLT(), SCIPresetConsAge(), SCIPvarGetLbLocal(), SCIPvarGetName(), SCIPvarGetStatus(), SCIPvarGetUbLocal(), and TRUE.

Referenced by SCIP_DECL_CONSPRESOL(), SCIP_DECL_CONSPROP(), and upgradeConss().

static void checkRedundancySide	(	SCIP *	scip,
		SCIP_VAR *	var,
		SCIP_VAR *	vbdvar,
		SCIP_Real	coef0,
		SCIP_Real	coef1,
		SCIP_Real	side0,
		SCIP_Real	side1,
		SCIP_Bool *	sideequal,
		SCIP_Bool *	cons0sidered,
		SCIP_Bool *	cons1sidered,
		SCIP_Bool	islhs
	)

static

Parameters

scip	SCIP data structure
var	variable x that has variable bound
vbdvar	binary, integer or implicit integer bounding variable y
coef0	coefficient c0 of bounding variable y for constraint 0
coef1	coefficient c1 of bounding variable y for constraint 1
side0	one side of variable bound inequality for constraint 0
side1	one side of variable bound inequality for constraint 1
sideequal	pointer to store if both constraints have the same redundancy on the given side
cons0sidered	pointer to store if side of constraint 0 is redundant
cons1sidered	pointer to store if side of constraint 1 is redundant
islhs	do we check the left or the right hand side

Definition at line 1475 of file cons_varbound.c.

References FALSE, MAX, MIN, NULL, REALABS, SCIP_Bool, SCIP_Real, SCIP_VARTYPE_CONTINUOUS, SCIPepsilon(), SCIPfeasCeil(), SCIPfeasFloor(), SCIPisFeasIntegral(), SCIPisInfinity(), SCIPisPositive(), SCIPvarGetLbGlobal(), SCIPvarGetType(), SCIPvarGetUbGlobal(), and TRUE.

Referenced by preprocessConstraintPairs().

static SCIP_RETCODE preprocessConstraintPairs	(	SCIP *	scip,
		SCIP_CONS **	conss,
		int	nconss,
		SCIP_Bool *	cutoff,
		int *	nchgbds,
		int *	ndelconss,
		int *	nchgcoefs,
		int *	nchgsides
	)

static

compares each constraint with all other constraints for possible redundancy and removes or changes constraint

we will order all constraint to have constraints with same variables next to each other to speed up presolving

consider two constraints like lhs1 <= x + b1*y <= rhs1 and lhs2 <= x + b2*y <= rhs2 we are doing the following presolving steps:

if( b1 == b2 ) newlhs = MAX(lhs1, lhs2) newrhs = MIN(rhs1, rhs2) updateSides delete one constraint else if( ((b1 > 0) == (b2 > 0)) && (lhs1 != -inf && lhs2 != -inf) || (rhs1 != inf && rhs2 != inf) )

 (i.e. both constraint have either a valid lhs or a valid rhs and infinity is on the same side and the
       coeffcients have the same size )

if( y is binary )
    if( lhs1 != -inf )
        newlhs = MAX(lhs1, lhs2)
        newb = newlhs - MAX(lhs1 - b1, lhs2 - b2)
    else
        newrhs = MIN(lhs1, lhs2)
        newb = newrhs - MIN(rhs1 - b1, rhs2 - b2)
    updateSidesAndCoef
    delete one constraint
else
    we calculate possible values for both variables and check which constraint is tighter

else nothing possible

We also try to tighten bounds in the case of two constraints lhs1 <= x + b1*y <= rhs1 and lhs2 <= y + b2*x <= rhs2. Eliminiating one variable and inserting into the second yields the following bounds: If b2 > 0: (1 - b1 * b2) * y >= lhs2 - b2 * rhs1 (1 - b1 * b2) * y <= rhs2 - b2 * lhs1 If b2 < 0: (1 - b1 * b2) * y >= lhs2 - b2 * lhs1 (1 - b1 * b2) * y <= rhs2 - b2 * rhs1 The case of x is similar.

Parameters

scip	SCIP data structure
conss	constraint set
nconss	number of constraints in constraint set
cutoff	pointer to store TRUE, if a cutoff was found
nchgbds	pointer to count number of bound changes
ndelconss	pointer to count number of deleted constraints
nchgcoefs	pointer to count the number of changed coefficients
nchgsides	pointer to count number of changed left/right hand sides

Definition at line 1823 of file cons_varbound.c.

References checkRedundancySide(), chgLhs(), chgRhs(), FALSE, MAX, MIN, NULL, REALABS, SCIP_Bool, SCIP_CALL, SCIP_OKAY, SCIP_Real, SCIP_UNKNOWN, SCIPadjustedVarLb(), SCIPadjustedVarUb(), SCIPconsGetData(), SCIPconsGetName(), SCIPconsIsActive(), SCIPconsIsLocked(), SCIPconsIsModifiable(), SCIPconsIsTransformed(), SCIPdebugMessage, SCIPdebugPrintCons, SCIPdelCons(), SCIPduplicateBufferArray, SCIPfreeBufferArray, SCIPinfinity(), SCIPisEQ(), SCIPisFeasLT(), SCIPisFeasNegative(), SCIPisFeasPositive(), SCIPisFeasZero(), SCIPisInfinity(), SCIPisNegative(), SCIPisPositive(), SCIPisZero(), SCIPlockVarCons(), SCIPsortPtr(), SCIPtightenVarLb(), SCIPtightenVarUb(), SCIPunlockVarCons(), SCIPupdateConsFlags(), SCIPvarGetLbGlobal(), SCIPvarGetName(), SCIPvarGetUbGlobal(), SCIPvarIsBinary(), and TRUE.

Referenced by SCIP_DECL_CONSPRESOL().

static SCIP_RETCODE prettifyConss	(	SCIP *	scip,
		SCIP_CONS **	conss,
		int	nconss,
		int *	nchgcoefs,
		int *	nchgsides
	)

static

for all varbound constraints with two integer variables make the coefficients integral

Parameters

scip	SCIP data structure
conss	constraint set
nconss	number of constraints in constraint set
nchgcoefs	pointer to count the number of changed coefficients
nchgsides	pointer to count number of changed left/right hand sides

Definition at line 2400 of file cons_varbound.c.

References FALSE, MAXSCALEDCOEF, MIN, NULL, REALABS, SCIP_Bool, SCIP_Longint, SCIP_OKAY, SCIP_Real, SCIP_VARTYPE_BINARY, SCIP_VARTYPE_IMPLINT, SCIP_VARTYPE_INTEGER, SCIPconsGetData(), SCIPconsIsDeleted(), SCIPdebugMessage, SCIPdebugPrintCons, SCIPepsilon(), SCIPfeastol(), SCIPgetNImplVars(), SCIPgetNIntVars(), SCIPinfinity(), SCIPisEQ(), SCIPisGE(), SCIPisInfinity(), SCIPisIntegral(), SCIPisLT(), SCIPrealToRational(), and SCIPvarGetType().

Referenced by SCIP_DECL_CONSPRESOL().

static SCIP_RETCODE applyFixings	(	SCIP *	scip,
		SCIP_CONS *	cons,
		SCIP_EVENTHDLR *	eventhdlr,
		SCIP_Bool *	cutoff,
		int *	nchgbds,
		int *	ndelconss,
		int *	naddconss
	)

static

replaces fixed and aggregated variables in variable bound constraint by active problem variables

Parameters

scip	SCIP data structure
cons	variable bound constraint
eventhdlr	event handler
cutoff	pointer to store whether an infeasibility was detected
nchgbds	pointer to count number of bound changes
ndelconss	pointer to count number of deleted constraints
naddconss	pointer to count number of added constraints

Definition at line 2560 of file cons_varbound.c.

References catchEvents(), dropEvents(), FALSE, NULL, SCIP_Bool, SCIP_CALL, SCIP_OKAY, SCIP_Real, SCIP_VARSTATUS_MULTAGGR, SCIPaddCoefLinear(), SCIPaddCons(), SCIPcaptureVar(), SCIPchgLhsLinear(), SCIPchgRhsLinear(), SCIPconsGetData(), SCIPconsGetName(), SCIPconsIsChecked(), SCIPconsIsDynamic(), SCIPconsIsEnforced(), SCIPconsIsInitial(), SCIPconsIsLocal(), SCIPconsIsModifiable(), SCIPconsIsPropagated(), SCIPconsIsRemovable(), SCIPconsIsSeparated(), SCIPconsIsStickingAtNode(), SCIPcreateConsLinear(), SCIPdebugMessage, SCIPdebugPrintCons, SCIPdelCons(), SCIPgetProbvarSum(), SCIPisFeasGT(), SCIPisFeasLT(), SCIPisInfinity(), SCIPisZero(), SCIPreleaseCons(), SCIPreleaseVar(), SCIPtightenVarLb(), SCIPtightenVarUb(), SCIPvarGetLbGlobal(), SCIPvarGetName(), SCIPvarGetStatus(), SCIPvarGetUbGlobal(), and TRUE.

Referenced by SCIP_DECL_CONSPRESOL(), and upgradeConss().

static SCIP_RETCODE tightenCoefs	(	SCIP *	scip,
		SCIP_CONS *	cons,
		int *	nchgcoefs,
		int *	nchgsides,
		int *	ndelconss
	)

static

tightens variable bound coefficient by inspecting the global bounds of the involved variables; note: this is also performed by the linear constraint handler - only necessary if the user directly creates variable bound constraints

Parameters

scip	SCIP data structure
cons	variable bound constraint
nchgcoefs	pointer to count the number of changed coefficients
nchgsides	pointer to count the number of left and right hand sides
ndelconss	pointer to count number of deleted constraints

Definition at line 2974 of file cons_varbound.c.

References FALSE, MAX, MIN, NULL, SCIP_CALL, SCIP_OKAY, SCIP_Real, SCIP_VARTYPE_BINARY, SCIP_VARTYPE_IMPLINT, SCIP_VARTYPE_INTEGER, SCIPconsGetData(), SCIPconsGetName(), SCIPdebugMessage, SCIPdelCons(), SCIPfeasCeil(), SCIPfeasFloor(), SCIPisEQ(), SCIPisFeasGE(), SCIPisFeasGT(), SCIPisFeasIntegral(), SCIPisFeasLE(), SCIPisFeasLT(), SCIPisGE(), SCIPisInfinity(), SCIPisIntegral(), SCIPisLE(), SCIPisZero(), SCIPvarGetLbGlobal(), SCIPvarGetName(), SCIPvarGetType(), SCIPvarGetUbGlobal(), SCIPvarIsBinary(), and TRUE.

Referenced by SCIP_DECL_CONSPRESOL(), and upgradeConss().

static SCIP_RETCODE upgradeConss	(	SCIP *	scip,
		SCIP_CONSHDLRDATA *	conshdlrdata,
		SCIP_CONS **	conss,
		int	nconss,
		SCIP_Bool *	cutoff,
		int *	naggrvars,
		int *	nchgbds,
		int *	nchgcoefs,
		int *	nchgsides,
		int *	ndelconss,
		int *	naddconss
	)

static

check if we can upgrade to a set-packing constraint

Parameters

scip	SCIP data structure
conshdlrdata	constraint handler data
conss	constraint set
nconss	number of constraints in constraint set
cutoff	pointer to store whether the node can be cut off
naggrvars	pointer to count the number of aggregated variables
nchgbds	pointer to count number of bound changes
nchgcoefs	pointer to count the number of changed coefficients
nchgsides	pointer to count the number of left and right hand sides
ndelconss	pointer to count the number of deleted constraints
naddconss	pointer to count the number of added constraints

Definition at line 3344 of file cons_varbound.c.

References applyFixings(), NULL, propagateCons(), REALABS, SCIP_Bool, SCIP_CALL, SCIP_OKAY, SCIPaddCons(), SCIPaggregateVars(), SCIPconsGetData(), SCIPconsGetName(), SCIPconsIsActive(), SCIPconsIsChecked(), SCIPconsIsDynamic(), SCIPconsIsEnforced(), SCIPconsIsInitial(), SCIPconsIsLocal(), SCIPconsIsModifiable(), SCIPconsIsPropagated(), SCIPconsIsRemovable(), SCIPconsIsSeparated(), SCIPconsIsStickingAtNode(), SCIPcreateConsSetpack(), SCIPdebugMessage, SCIPdebugPrintCons, SCIPdelCons(), SCIPgetNBinVars(), SCIPgetNegatedVar(), SCIPgetNImplVars(), SCIPisEQ(), SCIPisInfinity(), SCIPisLE(), SCIPisZero(), SCIPreleaseCons(), SCIPvarGetName(), SCIPvarIsBinary(), and tightenCoefs().

Referenced by SCIP_DECL_CONSPRESOL().

static SCIP_DECL_LINCONSUPGD ( linconsUpgdVarbound )

static

tries to upgrade a linear constraint into a variable bound constraint

Definition at line 3547 of file cons_varbound.c.

References NULL, REALABS, SCIP_Bool, SCIP_CALL, SCIP_OKAY, SCIP_Real, SCIPconsGetName(), SCIPconsIsChecked(), SCIPconsIsDynamic(), SCIPconsIsEnforced(), SCIPconsIsInitial(), SCIPconsIsLocal(), SCIPconsIsModifiable(), SCIPconsIsPropagated(), SCIPconsIsRemovable(), SCIPconsIsSeparated(), SCIPconsIsStickingAtNode(), SCIPcreateConsVarbound(), SCIPdebugMessage, SCIPinfinity(), SCIPisInfinity(), SCIPisIntegral(), SCIPisZero(), and SCIPvarGetType().

static SCIP_DECL_CONSHDLRCOPY ( conshdlrCopyVarbound )

static

copy method for constraint handler plugins (called when SCIP copies plugins)

Definition at line 3624 of file cons_varbound.c.

References CONSHDLR_NAME, NULL, SCIP_CALL, SCIP_OKAY, SCIPconshdlrGetName(), SCIPincludeConshdlrVarbound(), and TRUE.

static SCIP_DECL_CONSFREE ( consFreeVarbound )

static

destructor of constraint handler to free constraint handler data (called when SCIP is exiting)

Definition at line 3640 of file cons_varbound.c.

References CONSHDLR_NAME, conshdlrdataFree(), NULL, SCIP_OKAY, SCIPconshdlrGetData(), SCIPconshdlrGetName(), and SCIPconshdlrSetData().

static SCIP_DECL_CONSEXITSOL ( consExitsolVarbound )

static

solving process deinitialization method of constraint handler (called before branch and bound process data is freed)

Definition at line 3661 of file cons_varbound.c.

References NULL, SCIP_CALL, SCIP_OKAY, SCIPconsGetData(), and SCIPreleaseRow().

static SCIP_DECL_CONSDELETE ( consDeleteVarbound )

static

frees specific constraint data

Definition at line 3684 of file cons_varbound.c.

References consdataFree(), dropEvents(), NULL, SCIP_CALL, SCIP_OKAY, SCIPconshdlrGetData(), and SCIPisTransformed().

static SCIP_DECL_CONSTRANS ( consTransVarbound )

static

transforms constraint data into data belonging to the transformed problem

Definition at line 3705 of file cons_varbound.c.

References catchEvents(), consdataCreate(), NULL, SCIP_CALL, SCIP_OKAY, SCIPconsGetData(), SCIPconsGetName(), SCIPconshdlrGetData(), SCIPconsIsChecked(), SCIPconsIsDynamic(), SCIPconsIsEnforced(), SCIPconsIsInitial(), SCIPconsIsLocal(), SCIPconsIsModifiable(), SCIPconsIsPropagated(), SCIPconsIsRemovable(), SCIPconsIsSeparated(), SCIPconsIsStickingAtNode(), and SCIPcreateCons().

static SCIP_DECL_CONSINITLP ( consInitlpVarbound )

static

LP initialization method of constraint handler (called before the initial LP relaxation at a node is solved)

Definition at line 3739 of file cons_varbound.c.

References addRelaxation(), SCIP_CALL, SCIP_OKAY, and SCIPconsIsInitial().

static SCIP_DECL_CONSSEPALP ( consSepalpVarbound )

static

separation method of constraint handler for LP solutions

Definition at line 3755 of file cons_varbound.c.

References NULL, SCIP_CALL, SCIP_DIDNOTFIND, SCIP_OKAY, SCIPconshdlrGetData(), and separateCons().

static SCIP_DECL_CONSSEPASOL ( consSepasolVarbound )

static

separation method of constraint handler for arbitrary primal solutions

Definition at line 3785 of file cons_varbound.c.

References NULL, SCIP_CALL, SCIP_DIDNOTFIND, SCIP_OKAY, SCIPconshdlrGetData(), and separateCons().

static SCIP_DECL_CONSENFOLP ( consEnfolpVarbound )

static

constraint enforcing method of constraint handler for LP solutions

Definition at line 3815 of file cons_varbound.c.

References checkCons(), FALSE, NULL, SCIP_CALL, SCIP_FEASIBLE, SCIP_INFEASIBLE, SCIP_OKAY, SCIPconshdlrGetData(), SCIPincConsAge(), SCIPresetConsAge(), and separateCons().

static SCIP_DECL_CONSENFOPS ( consEnfopsVarbound )

static

constraint enforcing method of constraint handler for pseudo solutions

Definition at line 3855 of file cons_varbound.c.

References checkCons(), NULL, SCIP_CALL, SCIP_FEASIBLE, SCIP_INFEASIBLE, SCIP_OKAY, SCIPincConsAge(), SCIPresetConsAge(), and TRUE.

static SCIP_DECL_CONSCHECK ( consCheckVarbound )

static

feasibility check method of constraint handler for integral solutions

Definition at line 3882 of file cons_varbound.c.

References checkCons(), NULL, SCIP_CALL, SCIP_FEASIBLE, SCIP_INFEASIBLE, SCIP_OKAY, SCIP_Real, SCIPconsGetData(), SCIPgetSolVal(), SCIPinfoMessage(), SCIPisFeasGE(), SCIPisFeasLE(), and SCIPprintCons().

static SCIP_DECL_CONSPROP ( consPropVarbound )

static

domain propagation method of constraint handler

Definition at line 3925 of file cons_varbound.c.

References FALSE, NULL, propagateCons(), SCIP_Bool, SCIP_CALL, SCIP_CUTOFF, SCIP_DIDNOTFIND, SCIP_OKAY, SCIP_REDUCEDDOM, SCIPconshdlrGetData(), and SCIPunmarkConsPropagate().

static SCIP_DECL_CONSPRESOL ( consPresolVarbound )

static

presolving method of constraint handler

Definition at line 3961 of file cons_varbound.c.

References applyFixings(), CONSHDLR_NAME, FALSE, NULL, preprocessConstraintPairs(), prettifyConss(), propagateCons(), SCIP_Bool, SCIP_CALL, SCIP_CUTOFF, SCIP_DIDNOTFIND, SCIP_OKAY, SCIP_SUCCESS, SCIPaddVarVlb(), SCIPaddVarVub(), SCIPconsGetData(), SCIPconshdlrGetData(), SCIPconshdlrGetName(), SCIPconsIsActive(), SCIPconsIsModifiable(), SCIPdebugMessage, SCIPisInfinity(), SCIPisStopped(), SCIPvarGetName(), tightenCoefs(), TRUE, and upgradeConss().

static SCIP_DECL_CONSRESPROP ( consRespropVarbound )

static

propagation conflict resolving method of constraint handler

Definition at line 4112 of file cons_varbound.c.

References NULL, resolvePropagation(), SCIP_CALL, SCIP_OKAY, SCIP_SUCCESS, and SCIPconshdlrGetData().

static SCIP_DECL_CONSLOCK ( consLockVarbound )

static

variable rounding lock method of constraint handler

Definition at line 4131 of file cons_varbound.c.

References NULL, SCIP_CALL, SCIP_OKAY, SCIPaddVarLocks(), SCIPconsGetData(), and SCIPisInfinity().

static SCIP_DECL_CONSPRINT ( consPrintVarbound )

static

constraint display method of constraint handler

Definition at line 4169 of file cons_varbound.c.

References NULL, SCIP_OKAY, SCIP_VARTYPE_BINARY, SCIP_VARTYPE_BINARY_CHAR, SCIP_VARTYPE_CONTINUOUS_CHAR, SCIP_VARTYPE_IMPLINT, SCIP_VARTYPE_IMPLINT_CHAR, SCIP_VARTYPE_INTEGER, SCIP_VARTYPE_INTEGER_CHAR, SCIPconsGetData(), SCIPinfoMessage(), SCIPisEQ(), SCIPisInfinity(), SCIPvarGetName(), and SCIPvarGetType().

static SCIP_DECL_CONSCOPY ( consCopyVarbound )

static

constraint copying method of constraint handler

Definition at line 4211 of file cons_varbound.c.

References NULL, SCIP_CALL, SCIP_OKAY, SCIP_Real, SCIPallocBufferArray, SCIPconsGetName(), SCIPcopyConsLinear(), SCIPfreeBufferArray, SCIPgetLhsVarbound(), SCIPgetRhsVarbound(), SCIPgetVarVarbound(), SCIPgetVbdcoefVarbound(), and SCIPgetVbdvarVarbound().

static SCIP_DECL_CONSPARSE ( consParseVarbound )

static

constraint parsing method of constraint handler

Definition at line 4244 of file cons_varbound.c.

References FALSE, NULL, SCIP_Bool, SCIP_CALL, SCIP_OKAY, SCIP_Real, SCIPallocBufferArray, SCIPcreateConsVarbound(), SCIPdebugMessage, SCIPerrorMessage, SCIPfreeBufferArray, SCIPinfinity(), SCIPisEQ(), SCIPisInfinity(), SCIPparseVarsLinearsum(), SCIPstrToRealValue(), and SCIPvarGetName().

static SCIP_DECL_CONSGETVARS ( consGetVarsVarbound )

static

constraint method of constraint handler which returns the variables (if possible)

Definition at line 4367 of file cons_varbound.c.

References FALSE, NULL, SCIP_OKAY, SCIPconsGetData(), and TRUE.

static SCIP_DECL_CONSGETNVARS ( consGetNVarsVarbound )

static

constraint method of constraint handler which returns the number of variables (if possible)

Definition at line 4391 of file cons_varbound.c.

References SCIP_OKAY, and TRUE.

static SCIP_DECL_EVENTEXEC ( eventExecVarbound )

static

execution method of bound change event handler

Definition at line 4405 of file cons_varbound.c.

References FALSE, NULL, SCIP_CALL, SCIP_EVENTTYPE_BOUNDTIGHTENED, SCIP_EVENTTYPE_VARFIXED, SCIP_OKAY, SCIPconsGetData(), SCIPeventGetType(), and SCIPmarkConsPropagate().

SCIP_RETCODE SCIPincludeConshdlrVarbound ( SCIP * scip )

creates the handler for variable bound constraints and includes it in SCIP

Parameters

scip	SCIP data structure

Definition at line 4443 of file cons_varbound.c.

References CONSHDLR_CHECKPRIORITY, CONSHDLR_DELAYPRESOL, CONSHDLR_DELAYPROP, CONSHDLR_DELAYSEPA, CONSHDLR_DESC, CONSHDLR_EAGERFREQ, CONSHDLR_ENFOPRIORITY, CONSHDLR_MAXPREROUNDS, CONSHDLR_NAME, CONSHDLR_NEEDSCONS, CONSHDLR_PROP_TIMING, CONSHDLR_PROPFREQ, CONSHDLR_SEPAFREQ, CONSHDLR_SEPAPRIORITY, conshdlrdataCreate(), DEFAULT_MAXLPCOEF, DEFAULT_PRESOLPAIRWISE, DEFAULT_USEBDWIDENING, EVENTHDLR_DESC, EVENTHDLR_NAME, FALSE, LINCONSUPGD_PRIORITY, NULL, SCIP_CALL, SCIP_OKAY, SCIPaddBoolParam(), SCIPaddRealParam(), SCIPfindConshdlr(), SCIPincludeConshdlrBasic(), SCIPincludeEventhdlrBasic(), SCIPincludeLinconsUpgrade(), SCIPsetConshdlrCopy(), SCIPsetConshdlrDelete(), SCIPsetConshdlrExitsol(), SCIPsetConshdlrFree(), SCIPsetConshdlrGetNVars(), SCIPsetConshdlrGetVars(), SCIPsetConshdlrInitlp(), SCIPsetConshdlrParse(), SCIPsetConshdlrPresol(), SCIPsetConshdlrPrint(), SCIPsetConshdlrProp(), SCIPsetConshdlrResprop(), SCIPsetConshdlrSepa(), SCIPsetConshdlrTrans(), and TRUE.

Referenced by SCIP_DECL_CONSHDLRCOPY(), and SCIPincludeDefaultPlugins().

SCIP_RETCODE SCIPcreateConsVarbound	(	SCIP *	scip,
		SCIP_CONS **	cons,
		const char *	name,
		SCIP_VAR *	var,
		SCIP_VAR *	vbdvar,
		SCIP_Real	vbdcoef,
		SCIP_Real	lhs,
		SCIP_Real	rhs,
		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
	)

creates and captures a variable bound constraint: lhs <= x + c*y <= rhs

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
var	variable x that has variable bound
vbdvar	binary, integer or implicit integer bounding variable y
vbdcoef	coefficient c of bounding variable y
lhs	left hand side of variable bound inequality
rhs	right hand side of variable bound inequality
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.
modifiable	is constraint modifiable (subject to column generation)? Usually set to FALSE. In column generation applications, set to TRUE if pricing adds coefficients to this constraint.
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.

Definition at line 4509 of file cons_varbound.c.

References catchEvents(), consdataCreate(), CONSHDLR_NAME, NULL, SCIP_CALL, SCIP_OKAY, SCIP_PLUGINNOTFOUND, SCIPconshdlrGetData(), SCIPcreateCons(), SCIPerrorMessage, SCIPfindConshdlr(), and SCIPisTransformed().

Referenced by addVarbound(), createPrecedenceCons(), createVarUbs(), presolveTryAddLinearReform(), SCIP_DECL_CONSINITLP(), SCIP_DECL_CONSPARSE(), SCIP_DECL_CONSPRESOL(), SCIP_DECL_LINCONSUPGD(), and SCIPcreateConsBasicVarbound().

SCIP_RETCODE SCIPcreateConsBasicVarbound	(	SCIP *	scip,
		SCIP_CONS **	cons,
		const char *	name,
		SCIP_VAR *	var,
		SCIP_VAR *	vbdvar,
		SCIP_Real	vbdcoef,
		SCIP_Real	lhs,
		SCIP_Real	rhs
	)

creates and captures a variable bound constraint: lhs <= x + c*y <= rhs with all constraint flags set to their default values

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
var	variable x that has variable bound
vbdvar	binary, integer or implicit integer bounding variable y
vbdcoef	coefficient c of bounding variable y
lhs	left hand side of variable bound inequality
rhs	right hand side of variable bound inequality

Definition at line 4579 of file cons_varbound.c.

References FALSE, SCIP_CALL, SCIP_OKAY, SCIPcreateConsVarbound(), and TRUE.

SCIP_Real SCIPgetLhsVarbound	(	SCIP *	scip,
		SCIP_CONS *	cons
	)

gets left hand side of variable bound constraint lhs <= x + c*y <= rhs

Parameters

scip	SCIP data structure
cons	constraint data

Definition at line 4597 of file cons_varbound.c.

References CONSHDLR_NAME, NULL, SCIP_INVALID, SCIPABORT, SCIPconsGetData(), SCIPconsGetHdlr(), SCIPconshdlrGetName(), and SCIPerrorMessage.

Referenced by addVarboundConstraints(), checkVarbound(), initMatrix(), printRangeSection(), SCIP_DECL_CONSCOPY(), SCIP_DECL_READERWRITE(), SCIPwriteGms(), SCIPwriteLp(), SCIPwritePip(), writeFzn(), and writeOpbConstraints().

SCIP_Real SCIPgetRhsVarbound	(	SCIP *	scip,
		SCIP_CONS *	cons
	)

gets right hand side of variable bound constraint lhs <= x + c*y <= rhs

Parameters

scip	SCIP data structure
cons	constraint data

Definition at line 4618 of file cons_varbound.c.

References CONSHDLR_NAME, NULL, SCIP_INVALID, SCIPABORT, SCIPconsGetData(), SCIPconsGetHdlr(), SCIPconshdlrGetName(), and SCIPerrorMessage.

Referenced by addVarboundConstraints(), checkVarbound(), initMatrix(), printRangeSection(), SCIP_DECL_CONSCOPY(), SCIP_DECL_READERWRITE(), SCIPwriteGms(), SCIPwriteLp(), SCIPwritePip(), writeFzn(), and writeOpbConstraints().

SCIP_VAR* SCIPgetVarVarbound	(	SCIP *	scip,
		SCIP_CONS *	cons
	)

gets bounded variable x of variable bound constraint lhs <= x + c*y <= rhs

Parameters

scip	SCIP data structure
cons	constraint data

Definition at line 4639 of file cons_varbound.c.

References CONSHDLR_NAME, NULL, SCIPABORT, SCIPconsGetData(), SCIPconsGetHdlr(), SCIPconshdlrGetName(), and SCIPerrorMessage.

Referenced by addVarboundConstraints(), checkVarbound(), initMatrix(), SCIP_DECL_CONSCOPY(), SCIP_DECL_READERWRITE(), SCIPwriteCcg(), SCIPwriteGms(), SCIPwriteLp(), SCIPwritePbm(), SCIPwritePip(), SCIPwritePpm(), writeFzn(), and writeOpbConstraints().

SCIP_VAR* SCIPgetVbdvarVarbound	(	SCIP *	scip,
		SCIP_CONS *	cons
	)

gets bounding variable y of variable bound constraint lhs <= x + c*y <= rhs

Parameters

scip	SCIP data structure
cons	constraint data

Definition at line 4660 of file cons_varbound.c.

References CONSHDLR_NAME, NULL, SCIPABORT, SCIPconsGetData(), SCIPconsGetHdlr(), SCIPconshdlrGetName(), and SCIPerrorMessage.

Referenced by addVarboundConstraints(), checkVarbound(), initMatrix(), SCIP_DECL_CONSCOPY(), SCIP_DECL_READERWRITE(), SCIPwriteCcg(), SCIPwriteGms(), SCIPwriteLp(), SCIPwritePbm(), SCIPwritePip(), SCIPwritePpm(), writeFzn(), and writeOpbConstraints().

SCIP_Real SCIPgetVbdcoefVarbound	(	SCIP *	scip,
		SCIP_CONS *	cons
	)

gets bound coefficient c of variable bound constraint lhs <= x + c*y <= rhs

Parameters

scip	SCIP data structure
cons	constraint data

Definition at line 4681 of file cons_varbound.c.

References CONSHDLR_NAME, NULL, SCIP_INVALID, SCIPABORT, SCIPconsGetData(), SCIPconsGetHdlr(), SCIPconshdlrGetName(), and SCIPerrorMessage.

Referenced by addVarboundConstraints(), checkVarbound(), initMatrix(), SCIP_DECL_CONSCOPY(), SCIP_DECL_READERWRITE(), SCIPwriteCcg(), SCIPwriteGms(), SCIPwriteLp(), SCIPwritePbm(), SCIPwritePip(), SCIPwritePpm(), writeFzn(), and writeOpbConstraints().

SCIP_Real SCIPgetDualsolVarbound	(	SCIP *	scip,
		SCIP_CONS *	cons
	)

gets the dual solution of the variable bound constraint in the current LP

Parameters

scip	SCIP data structure
cons	constraint data

Definition at line 4702 of file cons_varbound.c.

References CONSHDLR_NAME, NULL, SCIP_INVALID, SCIPABORT, SCIPconsGetData(), SCIPconsGetHdlr(), SCIPconshdlrGetName(), SCIPerrorMessage, and SCIProwGetDualsol().

SCIP_Real SCIPgetDualfarkasVarbound	(	SCIP *	scip,
		SCIP_CONS *	cons
	)

gets the dual Farkas value of the variable bound constraint in the current infeasible LP

Parameters

scip	SCIP data structure
cons	constraint data

Definition at line 4726 of file cons_varbound.c.

References CONSHDLR_NAME, NULL, SCIP_INVALID, SCIPABORT, SCIPconsGetData(), SCIPconsGetHdlr(), SCIPconshdlrGetName(), SCIPerrorMessage, and SCIProwGetDualfarkas().

SCIP_ROW* SCIPgetRowVarbound	(	SCIP *	scip,
		SCIP_CONS *	cons
	)

returns the linear relaxation of the given variable bound constraint; may return NULL if no LP row was yet created; the user must not modify the row!

Parameters

scip	SCIP data structure
cons	constraint data

Definition at line 4752 of file cons_varbound.c.

References CONSHDLR_NAME, NULL, SCIPABORT, SCIPconsGetData(), SCIPconsGetHdlr(), SCIPconshdlrGetName(), and SCIPerrorMessage.

SCIP

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