sepa_strongcg.c File Reference

Detailed Description

Strong CG Cuts (Letchford & Lodi)

Author

Kati Wolter

Tobias Achterberg

Definition in file sepa_strongcg.c.

#include <assert.h>
#include <string.h>
#include "scip/sepa_strongcg.h"
#include "scip/pub_misc.h"

Go to the source code of this file.

Macros
#define	SEPA_NAME   "strongcg"
#define	SEPA_DESC   "Strong CG cuts separator (Letchford and Lodi)"
#define	SEPA_PRIORITY   -2000
#define	SEPA_FREQ   0
#define	SEPA_MAXBOUNDDIST   0.0
#define	SEPA_USESSUBSCIP   FALSE
#define	SEPA_DELAY   FALSE
#define	DEFAULT_MAXROUNDS   5
#define	DEFAULT_MAXROUNDSROOT   20
#define	DEFAULT_MAXSEPACUTS   50
#define	DEFAULT_MAXSEPACUTSROOT   500
#define	DEFAULT_DYNAMICCUTS   TRUE
#define	DEFAULT_MAXWEIGHTRANGE   1e+04
#define	MAKECUTINTEGRAL   /* try to scale all cuts to integral coefficients */
#define	FORCECUTINTEGRAL   /* discard cut if conversion to integral coefficients failed */
#define	SEPARATEROWS   /* separate rows with integral slack */
#define	BOUNDSWITCH   0.9999
#define	USEVBDS   TRUE
#define	ALLOWLOCAL   TRUE
#define	MAKECONTINTEGRAL   FALSE
#define	MINFRAC   0.05
#define	MAXFRAC   0.95
#define	MAXAGGRLEN(nvars)   (0.1*(nvars)+1000)

Functions
static SCIP_RETCODE	storeCutInArrays (SCIP *scip, int nvars, SCIP_VAR **vars, SCIP_Real *cutcoefs, SCIP_Real *varsolvals, char normtype, SCIP_VAR **cutvars, SCIP_Real *cutvals, int *cutlen, SCIP_Real *cutact, SCIP_Real *cutnorm)
static	SCIP_DECL_SEPACOPY (sepaCopyStrongcg)
static	SCIP_DECL_SEPAFREE (sepaFreeStrongcg)
static	SCIP_DECL_SEPAEXECLP (sepaExeclpStrongcg)
SCIP_RETCODE	SCIPincludeSepaStrongcg (SCIP *scip)

Macro Definition Documentation

SEPA_NAME

#define SEPA_NAME   "strongcg"

Definition at line 31 of file sepa_strongcg.c.

Referenced by SCIP_DECL_SEPACOPY(), SCIP_DECL_SEPAEXECLP(), SCIP_DECL_SEPAFREE(), and SCIPincludeSepaStrongcg().

SEPA_DESC

#define SEPA_DESC   "Strong CG cuts separator (Letchford and Lodi)"

Definition at line 32 of file sepa_strongcg.c.

Referenced by SCIPincludeSepaStrongcg().

SEPA_PRIORITY

#define SEPA_PRIORITY   -2000

Definition at line 33 of file sepa_strongcg.c.

Referenced by SCIPincludeSepaStrongcg().

SEPA_FREQ

#define SEPA_FREQ   0

Definition at line 34 of file sepa_strongcg.c.

Referenced by SCIPincludeSepaStrongcg().

SEPA_MAXBOUNDDIST

#define SEPA_MAXBOUNDDIST   0.0

Definition at line 35 of file sepa_strongcg.c.

Referenced by SCIPincludeSepaStrongcg().

SEPA_USESSUBSCIP

#define SEPA_USESSUBSCIP   FALSE

does the separator use a secondary SCIP instance?

Definition at line 36 of file sepa_strongcg.c.

Referenced by SCIPincludeSepaStrongcg().

SEPA_DELAY

#define SEPA_DELAY   FALSE

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

Definition at line 37 of file sepa_strongcg.c.

Referenced by SCIPincludeSepaStrongcg().

DEFAULT_MAXROUNDS

#define DEFAULT_MAXROUNDS   5

maximal number of strong CG separation rounds per node (-1: unlimited)

Definition at line 39 of file sepa_strongcg.c.

Referenced by SCIPincludeSepaStrongcg().

DEFAULT_MAXROUNDSROOT

#define DEFAULT_MAXROUNDSROOT   20

maximal number of strong CG separation rounds in the root node (-1: unlimited)

Definition at line 40 of file sepa_strongcg.c.

Referenced by SCIPincludeSepaStrongcg().

DEFAULT_MAXSEPACUTS

#define DEFAULT_MAXSEPACUTS   50

maximal number of strong CG cuts separated per separation round

Definition at line 41 of file sepa_strongcg.c.

Referenced by SCIPincludeSepaStrongcg().

DEFAULT_MAXSEPACUTSROOT

#define DEFAULT_MAXSEPACUTSROOT   500

maximal number of strong CG cuts separated per separation round in root node

Definition at line 42 of file sepa_strongcg.c.

Referenced by SCIPincludeSepaStrongcg().

DEFAULT_DYNAMICCUTS

#define DEFAULT_DYNAMICCUTS   TRUE

should generated cuts be removed from the LP if they are no longer tight?

Definition at line 43 of file sepa_strongcg.c.

Referenced by SCIPincludeSepaStrongcg().

DEFAULT_MAXWEIGHTRANGE

#define DEFAULT_MAXWEIGHTRANGE   1e+04

maximal valid range max(|weights|)/min(|weights|) of row weights

Definition at line 44 of file sepa_strongcg.c.

Referenced by SCIPincludeSepaStrongcg().

MAKECUTINTEGRAL

#define MAKECUTINTEGRAL   /* try to scale all cuts to integral coefficients */

Definition at line 46 of file sepa_strongcg.c.

FORCECUTINTEGRAL

#define FORCECUTINTEGRAL   /* discard cut if conversion to integral coefficients failed */

Definition at line 48 of file sepa_strongcg.c.

SEPARATEROWS

#define SEPARATEROWS   /* separate rows with integral slack */

Definition at line 49 of file sepa_strongcg.c.

BOUNDSWITCH

#define BOUNDSWITCH   0.9999

Definition at line 51 of file sepa_strongcg.c.

Referenced by SCIP_DECL_SEPAEXECLP().

USEVBDS

#define USEVBDS   TRUE

Definition at line 52 of file sepa_strongcg.c.

Referenced by SCIP_DECL_SEPAEXECLP().

ALLOWLOCAL

#define ALLOWLOCAL   TRUE

Definition at line 53 of file sepa_strongcg.c.

Referenced by SCIP_DECL_SEPAEXECLP().

MAKECONTINTEGRAL

#define MAKECONTINTEGRAL   FALSE

Definition at line 54 of file sepa_strongcg.c.

Referenced by SCIP_DECL_SEPAEXECLP().

MINFRAC

#define MINFRAC   0.05

Definition at line 55 of file sepa_strongcg.c.

Referenced by SCIP_DECL_SEPAEXECLP().

MAXFRAC

#define MAXFRAC   0.95

Definition at line 56 of file sepa_strongcg.c.

Referenced by SCIP_DECL_SEPAEXECLP().

MAXAGGRLEN

#define MAXAGGRLEN

(

nvars

)

(0.1*(nvars)+1000)

maximal length of base inequality

Definition at line 58 of file sepa_strongcg.c.

Referenced by SCIP_DECL_SEPAEXECLP().

Function Documentation

storeCutInArrays()

static SCIP_RETCODE storeCutInArrays ( SCIP *  scip, int  nvars, SCIP_VAR **  vars, SCIP_Real *  cutcoefs, SCIP_Real *  varsolvals, char  normtype, SCIP_VAR **  cutvars, SCIP_Real *  cutvals, int *  cutlen, SCIP_Real *  cutact, SCIP_Real *  cutnorm  )

static

stores nonzero elements of dense coefficient vector as sparse vector, and calculates activity and norm

Parameters

scip	SCIP data structure
nvars	number of problem variables
vars	problem variables
cutcoefs	dense coefficient vector
varsolvals	dense variable LP solution vector
normtype	type of norm to use for efficacy norm calculation
cutvars	array to store variables of sparse cut vector
cutvals	array to store coefficients of sparse cut vector
cutlen	pointer to store number of nonzero entries in cut
cutact	pointer to store activity of cut
cutnorm	pointer to store norm of cut vector

Definition at line 80 of file sepa_strongcg.c.

References MAX, NULL, SCIP_INVALIDDATA, SCIP_OKAY, SCIP_Real, SCIPerrorMessage, and SCIPisZero().

Referenced by SCIP_DECL_SEPAEXECLP().

SCIP_DECL_SEPACOPY()

static SCIP_DECL_SEPACOPY ( sepaCopyStrongcg  )

static

copy method for separator plugins (called when SCIP copies plugins)

Definition at line 193 of file sepa_strongcg.c.

References NULL, SCIP_CALL, SCIP_OKAY, SCIPincludeSepaStrongcg(), SCIPsepaGetName(), and SEPA_NAME.

SCIP_DECL_SEPAFREE()

static SCIP_DECL_SEPAFREE ( sepaFreeStrongcg  )

static

destructor of separator to free user data (called when SCIP is exiting)

Definition at line 207 of file sepa_strongcg.c.

References NULL, SCIP_OKAY, SCIPfreeBlockMemory, SCIPsepaGetData(), SCIPsepaGetName(), SCIPsepaSetData(), and SEPA_NAME.

SCIP_DECL_SEPAEXECLP()

static SCIP_DECL_SEPAEXECLP ( sepaExeclpStrongcg  )

static

LP solution separation method of separator

Definition at line 227 of file sepa_strongcg.c.

References ALLOWLOCAL, BOUNDSWITCH, FALSE, MAKECONTINTEGRAL, MAXAGGRLEN, MAXFRAC, MINFRAC, NULL, SCIP_Bool, SCIP_CALL, SCIP_CUTOFF, SCIP_DELAYED, SCIP_DIDNOTFIND, SCIP_DIDNOTRUN, SCIP_Longint, SCIP_LPSOLSTAT_OPTIMAL, SCIP_MAXSTRLEN, SCIP_OKAY, SCIP_Real, SCIP_SEPARATED, SCIP_VARSTATUS_COLUMN, SCIP_VARTYPE_CONTINUOUS, SCIPaddCut(), SCIPaddPoolCut(), SCIPaddVarsToRow(), SCIPallocBufferArray, SCIPcalcStrongCG(), SCIPcolGetPrimsol(), SCIPcolGetVar(), SCIPcreateEmptyRowSepa(), SCIPdebugMsg, SCIPepsilon(), SCIPfeasFrac(), SCIPfreeBufferArray, SCIPfreeBufferArrayNull, SCIPgetCharParam(), SCIPgetCutEfficacy(), SCIPgetDepth(), SCIPgetLPBasisInd(), SCIPgetLPBInvRow(), SCIPgetLPColsData(), SCIPgetLPRowsData(), SCIPgetLPSolstat(), SCIPgetMaxDepth(), SCIPgetNCutsFound(), SCIPgetNLPBranchCands(), SCIPgetNLPs(), SCIPgetRowActivity(), SCIPgetRowLPActivity(), SCIPgetRowMaxCoef(), SCIPgetRowMinCoef(), SCIPgetVarsData(), SCIPgetVarSol(), SCIPinfinity(), SCIPisCutEfficacious(), SCIPisEfficacious(), SCIPisFeasGT(), SCIPisLPSolBasic(), SCIPisPositive(), SCIPisStopped(), SCIPmakeRowIntegral(), SCIPreleaseRow(), SCIProwChgRank(), SCIProwGetName(), SCIProwGetNorm(), SCIProwGetRhs(), SCIProwIsIntegral(), SCIProwIsModifiable(), SCIPsepaGetData(), SCIPsepaGetName(), SCIPsepaGetNCallsAtNode(), SCIPsepaWasLPDelayed(), SCIPsnprintf(), SCIPsumepsilon(), SCIPvarGetLPSol(), SCIPvarGetName(), SCIPvarGetStatus(), SCIPvarGetType(), SCIPvarIsIntegral(), SEPA_NAME, storeCutInArrays(), TRUE, and USEVBDS.