Detailed Description

hybrid cut selector

Author: Leona Gottwald; Felipe Serrano; Mark Turner

#include <assert.h>
#include "scip/scip_cutsel.h"
#include "scip/scip_cut.h"
#include "scip/scip_lp.h"
#include "scip/scip_randnumgen.h"
#include "scip/cutsel_hybrid.h"

Go to the source code of this file.

Macros
#define	CUTSEL_NAME "hybrid"
#define	CUTSEL_DESC "weighted sum of efficacy, dircutoffdist, objparal, and intsupport"
#define	CUTSEL_PRIORITY 8000
#define	RANDSEED 0x5EED
#define	GOODSCORE 0.9
#define	BADSCORE 0.0
#define	DEFAULT_EFFICACYWEIGHT 1.0
#define	DEFAULT_DIRCUTOFFDISTWEIGHT 0.0
#define	DEFAULT_OBJPARALWEIGHT 0.1
#define	DEFAULT_INTSUPPORTWEIGHT 0.1
#define	DEFAULT_MINORTHO 0.90
#define	DEFAULT_MINORTHOROOT 0.90

Functions
static SCIP_Real	scoring (SCIP scip, SCIP_ROW cuts, SCIP_RANDNUMGEN randnumgen, SCIP_Real dircutoffdistweight, SCIP_Real efficacyweight, SCIP_Real objparalweight, SCIP_Real intsupportweight, int ncuts, SCIP_Real *scores)
static void	selectBestCut (SCIP_ROW *cuts, SCIP_Real scores, int ncuts)
static int	filterWithParallelism (SCIP_ROW cut, SCIP_ROW cuts, SCIP_Real scores, int ncuts, SCIP_Real goodscore, SCIP_Real goodmaxparall, SCIP_Real maxparall)
static	SCIP_DECL_CUTSELCOPY (cutselCopyHybrid)
static	SCIP_DECL_CUTSELFREE (cutselFreeHybrid)
static	SCIP_DECL_CUTSELINIT (cutselInitHybrid)
static	SCIP_DECL_CUTSELEXIT (cutselExitHybrid)
static	SCIP_DECL_CUTSELSELECT (cutselSelectHybrid)
SCIP_RETCODE	SCIPincludeCutselHybrid (SCIP *scip)
SCIP_RETCODE	SCIPselectCutsHybrid (SCIP scip, SCIP_ROW cuts, SCIP_ROW forcedcuts, SCIP_RANDNUMGEN randnumgen, SCIP_Real goodscorefac, SCIP_Real badscorefac, SCIP_Real goodmaxparall, SCIP_Real maxparall, SCIP_Real dircutoffdistweight, SCIP_Real efficacyweight, SCIP_Real objparalweight, SCIP_Real intsupportweight, int ncuts, int nforcedcuts, int maxselectedcuts, int *nselectedcuts)

Macro Definition Documentation

◆ CUTSEL_NAME

#define CUTSEL_NAME "hybrid"

Definition at line 44 of file cutsel_hybrid.c.

◆ CUTSEL_DESC

#define CUTSEL_DESC "weighted sum of efficacy, dircutoffdist, objparal, and intsupport"

Definition at line 45 of file cutsel_hybrid.c.

◆ CUTSEL_PRIORITY

#define CUTSEL_PRIORITY 8000

Definition at line 46 of file cutsel_hybrid.c.

◆ RANDSEED

#define RANDSEED 0x5EED

Definition at line 48 of file cutsel_hybrid.c.

◆ GOODSCORE

#define GOODSCORE 0.9

Definition at line 49 of file cutsel_hybrid.c.

Referenced by SCIPincludeCutselHybrid().

◆ BADSCORE

#define BADSCORE 0.0

Definition at line 50 of file cutsel_hybrid.c.

Referenced by SCIPincludeCutselHybrid().

◆ DEFAULT_EFFICACYWEIGHT

#define DEFAULT_EFFICACYWEIGHT 1.0

weight of efficacy in score calculation

Definition at line 52 of file cutsel_hybrid.c.

◆ DEFAULT_DIRCUTOFFDISTWEIGHT

#define DEFAULT_DIRCUTOFFDISTWEIGHT 0.0

weight of directed cutoff distance in score calculation

Definition at line 53 of file cutsel_hybrid.c.

◆ DEFAULT_OBJPARALWEIGHT

#define DEFAULT_OBJPARALWEIGHT 0.1

weight of objective parallelism in score calculation

Definition at line 54 of file cutsel_hybrid.c.

◆ DEFAULT_INTSUPPORTWEIGHT

#define DEFAULT_INTSUPPORTWEIGHT 0.1

weight of integral support in cut score calculation

Definition at line 55 of file cutsel_hybrid.c.

◆ DEFAULT_MINORTHO

#define DEFAULT_MINORTHO 0.90

minimal orthogonality for a cut to enter the LP

Definition at line 56 of file cutsel_hybrid.c.

◆ DEFAULT_MINORTHOROOT

#define DEFAULT_MINORTHOROOT 0.90

minimal orthogonality for a cut to enter the LP in the root node

Definition at line 57 of file cutsel_hybrid.c.

Referenced by SCIPincludeCutselHybrid().

Function Documentation

◆ scoring()

SCIP_Real scoring	(	SCIP *	scip,
		SCIP_ROW **	cuts,
		SCIP_RANDNUMGEN *	randnumgen,
		SCIP_Real	dircutoffdistweight,
		SCIP_Real	efficacyweight,
		SCIP_Real	objparalweight,
		SCIP_Real	intsupportweight,
		int	ncuts,
		SCIP_Real *	scores )

static

returns the maximum score of cuts; if scores is not NULL, then stores the individual score of each cut in scores

Parameters

scip	SCIP data structure
cuts	array with cuts to score
randnumgen	random number generator for tie-breaking, or NULL
dircutoffdistweight	weight of directed cutoff distance in cut score calculation
efficacyweight	weight of efficacy in cut score calculation
objparalweight	weight of objective parallelism in cut score calculation
intsupportweight	weight of integral support in cut score calculation
ncuts	number of cuts in cuts array
scores	array to store the score of cuts or NULL

Definition at line 85 of file cutsel_hybrid.c.

References i, MAX, NULL, SCIP_Real, SCIPgetBestSol(), SCIPgetCutEfficacy(), SCIPgetCutLPSolCutoffDistance(), SCIPgetRowNumIntCols(), SCIPgetRowObjParallelism(), SCIPrandomGetReal(), SCIProwGetNNonz(), SCIProwIsInGlobalCutpool(), SCIProwIsLocal(), and sol.

Referenced by SCIPselectCutsHybrid().

◆ selectBestCut()

void selectBestCut	(	SCIP_ROW **	cuts,
		SCIP_Real *	scores,
		int	ncuts )

static

move the cut with the highest score to the first position in the array; there must be at least one cut

Parameters

cuts	array with cuts to perform selection algorithm
scores	array with scores of cuts to perform selection algorithm
ncuts	number of cuts in given array

Definition at line 201 of file cutsel_hybrid.c.

References assert(), i, NULL, SCIP_Real, SCIPswapPointers(), and SCIPswapReals().

Referenced by SCIPselectCutsHybrid().

◆ filterWithParallelism()

int filterWithParallelism	(	SCIP_ROW *	cut,
		SCIP_ROW **	cuts,
		SCIP_Real *	scores,
		int	ncuts,
		SCIP_Real	goodscore,
		SCIP_Real	goodmaxparall,
		SCIP_Real	maxparall )

static

filters the given array of cuts to enforce a maximum parallelism constraint w.r.t the given cut; moves filtered cuts to the end of the array and returns number of selected cuts

Parameters

cut	cut to filter orthogonality with
cuts	array with cuts to perform selection algorithm
scores	array with scores of cuts to perform selection algorithm
ncuts	number of cuts in given array
goodscore	threshold for the score to be considered a good cut
goodmaxparall	maximal parallelism for good cuts
maxparall	maximal parallelism for all cuts that are not good

Definition at line 234 of file cutsel_hybrid.c.

References assert(), i, NULL, SCIP_Real, SCIProwGetParallelism(), SCIPswapPointers(), and SCIPswapReals().

Referenced by SCIPselectCutsHybrid().

◆ SCIP_DECL_CUTSELCOPY()

SCIP_DECL_CUTSELCOPY ( cutselCopyHybrid )

static

copy method for cut selector plugin (called when SCIP copies plugins)

Definition at line 277 of file cutsel_hybrid.c.

References assert(), CUTSEL_NAME, NULL, SCIP_CALL, SCIP_OKAY, SCIPcutselGetName(), and SCIPincludeCutselHybrid().

◆ SCIP_DECL_CUTSELFREE()

SCIP_DECL_CUTSELFREE ( cutselFreeHybrid )

static

destructor of cut selector to free user data (called when SCIP is exiting) ! [SnippetCutselFreeHybrid]

Definition at line 292 of file cutsel_hybrid.c.

References NULL, SCIP_OKAY, SCIPcutselGetData(), SCIPcutselSetData(), and SCIPfreeBlockMemory.

◆ SCIP_DECL_CUTSELINIT()

SCIP_DECL_CUTSELINIT ( cutselInitHybrid )

static

! [SnippetCutselFreeHybrid] initialization method of cut selector (called after problem was transformed)

Definition at line 308 of file cutsel_hybrid.c.

References assert(), NULL, RANDSEED, SCIP_CALL, SCIP_OKAY, SCIPcreateRandom(), SCIPcutselGetData(), and TRUE.

◆ SCIP_DECL_CUTSELEXIT()

SCIP_DECL_CUTSELEXIT ( cutselExitHybrid )

static

deinitialization method of cut selector (called before transformed problem is freed)

Definition at line 322 of file cutsel_hybrid.c.

References assert(), NULL, SCIP_OKAY, SCIPcutselGetData(), and SCIPfreeRandom().

◆ SCIP_DECL_CUTSELSELECT()

SCIP_DECL_CUTSELSELECT ( cutselSelectHybrid )

static

cut selection method of cut selector

Definition at line 337 of file cutsel_hybrid.c.

References assert(), MAX, NULL, result, SCIP_CALL, SCIP_OKAY, SCIP_Real, SCIP_SUCCESS, SCIPcutselGetData(), and SCIPselectCutsHybrid().

Detailed Description

Macros

Functions

Macro Definition Documentation

◆ CUTSEL_NAME

◆ CUTSEL_DESC

◆ CUTSEL_PRIORITY

◆ RANDSEED

◆ GOODSCORE

◆ BADSCORE

◆ DEFAULT_EFFICACYWEIGHT

◆ DEFAULT_DIRCUTOFFDISTWEIGHT

◆ DEFAULT_OBJPARALWEIGHT

◆ DEFAULT_INTSUPPORTWEIGHT

◆ DEFAULT_MINORTHO

◆ DEFAULT_MINORTHOROOT

Function Documentation

◆ scoring()

◆ selectBestCut()

◆ filterWithParallelism()

◆ SCIP_DECL_CUTSELCOPY()

◆ SCIP_DECL_CUTSELFREE()

◆ SCIP_DECL_CUTSELINIT()

◆ SCIP_DECL_CUTSELEXIT()

◆ SCIP_DECL_CUTSELSELECT()