Detailed Description

constraint handler for ensuring that primal solution is exact

Author: Antonia Chmiela; Leon Eifler

#include <assert.h>
#include "scip/def.h"
#include "scip/cons_exactlinear.h"
#include "scip/cons_exactsol.h"
#include "scip/pub_cons.h"
#include "scip/pub_heur.h"
#include "scip/pub_lp.h"
#include "scip/pub_lpexact.h"
#include "scip/pub_message.h"
#include "scip/pub_misc.h"
#include "scip/pub_sol.h"
#include "scip/pub_var.h"
#include "scip/rational.h"
#include "scip/scip_certificate.h"
#include "scip/scip_cons.h"
#include "scip/scip_exact.h"
#include "scip/scip_general.h"
#include "scip/scip_lp.h"
#include "scip/scip_lpexact.h"
#include "scip/scip_mem.h"
#include "scip/scip_message.h"
#include "scip/scip_numerics.h"
#include "scip/scip_param.h"
#include "scip/scip_prob.h"
#include "scip/scip_solvingstats.h"
#include "scip/scip_tree.h"
#include "scip/set.h"

Go to the source code of this file.

Data Structures
struct	SolIntAssignment

Macros
#define	CONSHDLR_NAME "exactsol"

#define	CONSHDLR_DESC "constraint handler for repairing floating-point primal solutions to satisfy exact feasibility"

#define	CONSHDLR_ENFOPRIORITY -9999999

#define	CONSHDLR_CHECKPRIORITY -999999

#define	CONSHDLR_EAGERFREQ 100

#define	CONSHDLR_NEEDSCONS FALSE

#define	DEFAULT_CHECKFPFEASIBILITY TRUE

#define	DEFAULT_CHECKCONTIMPLINT TRUE

#define	DEFAULT_ABORTFRAC 1e-9

#define	DEFAULT_UNFIXFRAC 0.0

#define	DEFAULT_MAXSTALLS 1000

#define	DEFAULT_SOLBUFSIZE 10

#define	DEFAULT_MINIMPROVE 0.2

Typedefs
typedef struct SolIntAssignment	SOLINTASSIGNMENT

Functions
static	SCIP_DECL_HASHGETKEY (hashGetKeyAssignment)

static	SCIP_DECL_HASHKEYEQ (hashKeyEqAssignment)

static	SCIP_DECL_HASHKEYVAL (hashKeyValAssignment)

static SCIP_RETCODE	bufferSolution (SCIP scip, SCIP_SOL sol, SCIP_CONSHDLRDATA *conshdlrdata)

static void	clearSoluBuffer (SCIP scip, SCIP_CONSHDLRDATA conshdlrdata)

static SCIP_RETCODE	solCreateSolAssignment (SCIP scip, SCIP_SOL sol, SCIP_Bool checkcontimplint, SOLINTASSIGNMENT **assignment)

static void	solFreeAssignment (SCIP scip, SOLINTASSIGNMENT *assignment)

static void	checkProbHasContEqs (SCIP scip, SCIP_CONSHDLRDATA conshdlrdata)

static	SCIP_DECL_CONSENFOLP (consEnfolpExactSol)

static	SCIP_DECL_CONSENFORELAX (consEnforelaxExactSol)

static	SCIP_DECL_CONSENFOPS (consEnfopsExactSol)

static	SCIP_DECL_CONSCHECK (consCheckExactSol)

static	SCIP_DECL_CONSLOCK (consLockExactSol)

static	SCIP_DECL_CONSFREE (consFreeExactSol)

static	SCIP_DECL_CONSINIT (consInitExactSol)

static	SCIP_DECL_CONSEXIT (consExitExactSol)

static	SCIP_DECL_CONSHDLRCOPY (conshdlrCopyExactSol)

SCIP_RETCODE	SCIPincludeConshdlrExactSol (SCIP *scip)

Macro Definition Documentation

◆ CONSHDLR_NAME

#define CONSHDLR_NAME "exactsol"

Definition at line 65 of file cons_exactsol.c.

◆ CONSHDLR_DESC

#define CONSHDLR_DESC "constraint handler for repairing floating-point primal solutions to satisfy exact feasibility"

Definition at line 66 of file cons_exactsol.c.

◆ CONSHDLR_ENFOPRIORITY

#define CONSHDLR_ENFOPRIORITY -9999999

priority of the constraint handler for constraint enforcing

Definition at line 67 of file cons_exactsol.c.

◆ CONSHDLR_CHECKPRIORITY

#define CONSHDLR_CHECKPRIORITY -999999

priority of the constraint handler for checking feasibility

Definition at line 68 of file cons_exactsol.c.

◆ CONSHDLR_EAGERFREQ

#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 70 of file cons_exactsol.c.

◆ CONSHDLR_NEEDSCONS

#define CONSHDLR_NEEDSCONS FALSE

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

Definition at line 71 of file cons_exactsol.c.

◆ DEFAULT_CHECKFPFEASIBILITY

#define DEFAULT_CHECKFPFEASIBILITY TRUE

should a solution be checked in floating-point arithmetic prior to being processed?

Definition at line 73 of file cons_exactsol.c.

◆ DEFAULT_CHECKCONTIMPLINT

#define DEFAULT_CHECKCONTIMPLINT TRUE

should integrality of continuous implied integral variables be ensured?

Definition at line 75 of file cons_exactsol.c.

◆ DEFAULT_ABORTFRAC

#define DEFAULT_ABORTFRAC 1e-9

fractionality of enforced integral value above which reparation is aborted

Definition at line 77 of file cons_exactsol.c.

◆ DEFAULT_UNFIXFRAC

#define DEFAULT_UNFIXFRAC 0.0

fractionality of weakly implied value up to which reparation fixes variable

Definition at line 79 of file cons_exactsol.c.

◆ DEFAULT_MAXSTALLS

#define DEFAULT_MAXSTALLS 1000

maximal number of consecutive repair calls without success

Definition at line 80 of file cons_exactsol.c.

◆ DEFAULT_SOLBUFSIZE

#define DEFAULT_SOLBUFSIZE 10

size of solution buffer

Definition at line 81 of file cons_exactsol.c.

◆ DEFAULT_MINIMPROVE

#define DEFAULT_MINIMPROVE 0.2

minimal percentage of primal improvement to trigger solution processing

Definition at line 82 of file cons_exactsol.c.

Typedef Documentation

◆ SOLINTASSIGNMENT

typedef struct SolIntAssignment SOLINTASSIGNMENT

Definition at line 91 of file cons_exactsol.c.

Function Documentation

◆ SCIP_DECL_HASHGETKEY()

static SCIP_DECL_HASHGETKEY ( hashGetKeyAssignment )

static

gets the key of the given element

Definition at line 115 of file cons_exactsol.c.

◆ SCIP_DECL_HASHKEYEQ()

static SCIP_DECL_HASHKEYEQ ( hashKeyEqAssignment )

static

returns TRUE iff both keys are equal

Definition at line 123 of file cons_exactsol.c.

References FALSE, SolIntAssignment::idx, SolIntAssignment::len, NULL, TRUE, and SolIntAssignment::vals.

◆ SCIP_DECL_HASHKEYVAL()

static SCIP_DECL_HASHKEYVAL ( hashKeyValAssignment )

static

returns the hash value of the key

Definition at line 149 of file cons_exactsol.c.

References SolIntAssignment::idx, SolIntAssignment::len, SCIPhashSignature64, and SolIntAssignment::vals.

◆ bufferSolution()

static SCIP_RETCODE bufferSolution	(	SCIP *	scip,
		SCIP_SOL *	sol,
		SCIP_CONSHDLRDATA *	conshdlrdata
	)

static

unlinks and copies a solution and adds it to the solution buffer

Parameters

scip	SCIP data structure
sol	solution to add
conshdlrdata	exactsol constraint handler data

Definition at line 165 of file cons_exactsol.c.

References SCIP_CALL, SCIP_OKAY, SCIPcreateSolCopy(), SCIPdebugMessage, SCIPheurGetName(), SCIPreallocBlockMemoryArray, SCIPsolGetHeur(), and SCIPunlinkSol().

Referenced by SCIP_DECL_CONSCHECK().

◆ clearSoluBuffer()

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

static

frees all remaining solutions in buffer

Parameters

scip	SCIP data structure
conshdlrdata	exactsol constraint handler data

Definition at line 195 of file cons_exactsol.c.

References SCIP_CALL_ABORT, and SCIPfreeSol().

Referenced by SCIP_DECL_CONSCHECK().

◆ solCreateSolAssignment()

static SCIP_RETCODE solCreateSolAssignment	(	SCIP *	scip,
		SCIP_SOL *	sol,
		SCIP_Bool	checkcontimplint,
		SOLINTASSIGNMENT **	assignment
	)

static

creates assignment from integer variable-values in solution

Parameters

scip	SCIP data structure
sol	solution to create assignment for
checkcontimplint	whether continuous implied integral variables should be included
assignment	address of assignment

Definition at line 212 of file cons_exactsol.c.

References NULL, SCIP_CALL, SCIP_Longint, SCIP_OKAY, SCIPallocBlockMemory, SCIPallocClearBlockMemoryArray, SCIPgetSolVal(), SCIPgetSolVarsData(), SCIPround(), SCIPvarGetIndex(), and SCIPvarIsIntegral().

Referenced by SCIP_DECL_CONSCHECK().

◆ solFreeAssignment()

static void solFreeAssignment	(	SCIP *	scip,
		SOLINTASSIGNMENT **	assignment
	)

static

creates assignment from integer variable-values in solution

Parameters

scip	SCIP data structure
assignment	address of assignment

Definition at line 263 of file cons_exactsol.c.

References NULL, SCIPfreeBlockMemory, and SCIPfreeBlockMemoryArray.

Referenced by SCIP_DECL_CONSCHECK().

◆ checkProbHasContEqs()

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

static

checks whether equation constraints with non-integral variables are present

Parameters

scip	SCIP data structure
conshdlrdata	exactsol constraint handler data

Definition at line 278 of file cons_exactsol.c.

References NULL, SCIP_Bool, SCIPABORT, SCIPconsGetHdlr(), SCIPconsGetLhsExact(), SCIPconsGetRhsExact(), SCIPconshdlrGetName(), SCIPerrorMessage, SCIPfindConshdlr(), SCIPgetConss(), SCIPgetNConss(), SCIPgetNVarsExactLinear(), SCIPgetVarsExactLinear(), SCIPrationalIsEQ(), SCIPvarIsIntegral(), and TRUE.

Referenced by SCIP_DECL_CONSCHECK().

◆ SCIP_DECL_CONSENFOLP()

static SCIP_DECL_CONSENFOLP ( consEnfolpExactSol )

static

constraint enforcing method of constraint handler for LP solutions

Definition at line 339 of file cons_exactsol.c.

References NULL, SCIP_FEASIBLE, SCIP_OKAY, and SCIPisExact().

◆ SCIP_DECL_CONSENFORELAX()

static SCIP_DECL_CONSENFORELAX ( consEnforelaxExactSol )

static

constraint enforcing method of constraint handler for LP solutions

Definition at line 352 of file cons_exactsol.c.

References NULL, SCIP_FEASIBLE, SCIP_OKAY, and SCIPisExact().

◆ SCIP_DECL_CONSENFOPS()

static SCIP_DECL_CONSENFOPS ( consEnfopsExactSol )

static

constraint enforcing method of constraint handler for pseudo solutions

Definition at line 365 of file cons_exactsol.c.

References NULL, SCIP_FEASIBLE, SCIP_OKAY, and SCIPisExact().

◆ SCIP_DECL_CONSCHECK()

static SCIP_DECL_CONSCHECK ( consCheckExactSol )

static

feasibility check method of constraint handler for integral solutions

Definition at line 378 of file cons_exactsol.c.

References bufferSolution(), checkProbHasContEqs(), clearSoluBuffer(), DEFAULT_SOLBUFSIZE, EPSISINT, FALSE, NULL, SCIP_Bool, SCIP_CALL, SCIP_FEASIBLE, SCIP_IMPLINTTYPE_WEAK, SCIP_INFEASIBLE, SCIP_LPSOLSTAT_OPTIMAL, SCIP_NODETYPE_FOCUSNODE, SCIP_OKAY, SCIP_R_ROUND_NEAREST, SCIP_Real, SCIP_SOLTYPE_HEUR, SCIP_STAGE_SOLVING, SCIP_VARSTATUS_COLUMN, SCIP_VARTYPE_CONTINUOUS, SCIPbuffer(), SCIPchgVarLbDive(), SCIPchgVarLbExactDive(), SCIPchgVarUbDive(), SCIPchgVarUbExactDive(), SCIPconsGetRow(), SCIPconshdlrGetData(), SCIPconstructLP(), SCIPcreateLPSolExact(), SCIPdebug, SCIPdebugMessage, SCIPendExactDive(), SCIPflushLP(), SCIPfreeSol(), SCIPgetConss(), SCIPgetCurrentNode(), SCIPgetLPExactSolstat(), SCIPgetNConss(), SCIPgetNContImplVars(), SCIPgetNContVars(), SCIPgetNVars(), SCIPgetRowSolActivity(), SCIPgetSolTransObj(), SCIPgetSolVal(), SCIPgetStage(), SCIPgetUpperbound(), SCIPgetVars(), SCIPhasCurrentNodeLP(), SCIPhashtableExists(), SCIPhashtableInsert(), SCIPheurGetName(), SCIPinDive(), SCIPinExactDive(), SCIPisExact(), SCIPisExactDivePossible(), SCIPisFeasGT(), SCIPisFeasLT(), SCIPisLPConstructed(), SCIPisLT(), SCIPnodeGetType(), SCIPoverwriteFPsol(), SCIPprintSol(), SCIPrationalCreateBuffer(), SCIPrationalFreeBuffer(), SCIPrationalIsLE(), SCIPrationalRoundInteger(), SCIPrationalSetReal(), SCIPreallocBlockMemoryArray, SCIPround(), SCIProwGetLhs(), SCIProwGetRhs(), SCIPsolGetHeur(), SCIPsolGetType(), SCIPsolIsExact(), SCIPsolSetHeur(), SCIPsolveExactDiveLP(), SCIPsortPtr(), SCIPstartExactDive(), SCIPtrySolFreeExact(), SCIPvarGetImplType(), SCIPvarGetLbGlobal(), SCIPvarGetLbGlobalExact(), SCIPvarGetLbLocalExact(), SCIPvarGetStatusExact(), SCIPvarGetType(), SCIPvarGetUbGlobal(), SCIPvarGetUbGlobalExact(), SCIPvarGetUbLocalExact(), SCIPvarIsIntegral(), SCIPwarningMessage(), solCreateSolAssignment(), solFreeAssignment(), and TRUE.

◆ SCIP_DECL_CONSLOCK()

static SCIP_DECL_CONSLOCK ( consLockExactSol )

static

variable rounding lock method of constraint handler

Definition at line 730 of file cons_exactsol.c.

References SCIP_OKAY.

◆ SCIP_DECL_CONSFREE()

static SCIP_DECL_CONSFREE ( consFreeExactSol )

static

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

Definition at line 738 of file cons_exactsol.c.

References NULL, SCIP_OKAY, SCIPconshdlrGetData(), SCIPconshdlrSetData(), and SCIPfreeBlockMemory.

◆ SCIP_DECL_CONSINIT()

static SCIP_DECL_CONSINIT ( consInitExactSol )

static

initialization method of constraint handler (called after problem was transformed)

Definition at line 755 of file cons_exactsol.c.

References DEFAULT_SOLBUFSIZE, NULL, SCIP_CALL, SCIP_OKAY, SCIPallocBlockMemoryArray, SCIPblkmem(), SCIPconshdlrGetData(), SCIPconshdlrSetNeedsCons(), SCIPhashtableCreate(), SCIPisExact(), and TRUE.

◆ SCIP_DECL_CONSEXIT()

static SCIP_DECL_CONSEXIT ( consExitExactSol )

static

deinitialization method of constraint handler (called before transformed problem is freed)

Definition at line 792 of file cons_exactsol.c.

References FALSE, NULL, SCIP_CALL, SCIP_OKAY, SCIPconshdlrGetData(), SCIPconshdlrNeedsCons(), SCIPconshdlrSetNeedsCons(), SCIPfreeBlockMemory, SCIPfreeBlockMemoryArray, SCIPfreeSol(), SCIPhashtableFree(), SCIPhashtableRemoveAll(), and SCIPisExact().

◆ SCIP_DECL_CONSHDLRCOPY()

static SCIP_DECL_CONSHDLRCOPY ( conshdlrCopyExactSol )

static

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

Definition at line 836 of file cons_exactsol.c.

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

SCIP

Detailed Description

Data Structures

Macros

Typedefs

Functions

Macro Definition Documentation

◆ CONSHDLR_NAME

◆ CONSHDLR_DESC

◆ CONSHDLR_ENFOPRIORITY

◆ CONSHDLR_CHECKPRIORITY

◆ CONSHDLR_EAGERFREQ

◆ CONSHDLR_NEEDSCONS

◆ DEFAULT_CHECKFPFEASIBILITY

◆ DEFAULT_CHECKCONTIMPLINT

◆ DEFAULT_ABORTFRAC

◆ DEFAULT_UNFIXFRAC

◆ DEFAULT_MAXSTALLS

◆ DEFAULT_SOLBUFSIZE

◆ DEFAULT_MINIMPROVE

Typedef Documentation

◆ SOLINTASSIGNMENT

Function Documentation

◆ SCIP_DECL_HASHGETKEY()

◆ SCIP_DECL_HASHKEYEQ()

◆ SCIP_DECL_HASHKEYVAL()

◆ bufferSolution()

◆ clearSoluBuffer()

◆ solCreateSolAssignment()

◆ solFreeAssignment()

◆ checkProbHasContEqs()

◆ SCIP_DECL_CONSENFOLP()

◆ SCIP_DECL_CONSENFORELAX()

◆ SCIP_DECL_CONSENFOPS()

◆ SCIP_DECL_CONSCHECK()

◆ SCIP_DECL_CONSLOCK()

◆ SCIP_DECL_CONSFREE()

◆ SCIP_DECL_CONSINIT()

◆ SCIP_DECL_CONSEXIT()

◆ SCIP_DECL_CONSHDLRCOPY()