heur_objpscostdiving.c File Reference

Detailed Description

LP diving heuristic that changes variable's objective value instead of bounds, using pseudo cost values as guide.

Author

Tobias Achterberg

Definition in file heur_objpscostdiving.c.

#include <assert.h>
#include <string.h>
#include "scip/heur_objpscostdiving.h"

Go to the source code of this file.

Macros
#define	HEUR_NAME   "objpscostdiving"
#define	HEUR_DESC   "LP diving heuristic that changes variable's objective values instead of bounds, using pseudo costs as guide"
#define	HEUR_DISPCHAR   'o'
#define	HEUR_PRIORITY   -1004000
#define	HEUR_FREQ   20
#define	HEUR_FREQOFS   4
#define	HEUR_MAXDEPTH   -1
#define	HEUR_TIMING   SCIP_HEURTIMING_AFTERLPPLUNGE
#define	HEUR_USESSUBSCIP   FALSE
#define	DEFAULT_MINRELDEPTH   0.0
#define	DEFAULT_MAXRELDEPTH   1.0
#define	DEFAULT_MAXLPITERQUOT   0.01
#define	DEFAULT_MAXLPITEROFS   1000
#define	DEFAULT_MAXSOLS   -1
#define	DEFAULT_DEPTHFAC   0.5
#define	DEFAULT_DEPTHFACNOSOL   2.0
#define	MINLPITER   10000

Functions
static void	calcPscostQuot (SCIP *scip, SCIP_VAR *var, SCIP_Real primsol, SCIP_Real frac, int rounddir, SCIP_Real *pscostquot, SCIP_Bool *roundup)
static	SCIP_DECL_HEURCOPY (heurCopyObjpscostdiving)
static	SCIP_DECL_HEURFREE (heurFreeObjpscostdiving)
static	SCIP_DECL_HEURINIT (heurInitObjpscostdiving)
static	SCIP_DECL_HEUREXIT (heurExitObjpscostdiving)
static	SCIP_DECL_HEUREXEC (heurExecObjpscostdiving)
SCIP_RETCODE	SCIPincludeHeurObjpscostdiving (SCIP *scip)

Macro Definition Documentation

#define HEUR_NAME   "objpscostdiving"

Definition at line 29 of file heur_objpscostdiving.c.

Referenced by SCIP_DECL_HEURCOPY(), SCIP_DECL_HEUREXEC(), SCIP_DECL_HEUREXIT(), SCIP_DECL_HEURFREE(), SCIP_DECL_HEURINIT(), and SCIPincludeHeurObjpscostdiving().

#define HEUR_DESC   "LP diving heuristic that changes variable's objective values instead of bounds, using pseudo costs as guide"

Definition at line 30 of file heur_objpscostdiving.c.

Referenced by SCIPincludeHeurObjpscostdiving().

#define HEUR_DISPCHAR   'o'

Definition at line 31 of file heur_objpscostdiving.c.

Referenced by SCIPincludeHeurObjpscostdiving().

#define HEUR_PRIORITY   -1004000

Definition at line 32 of file heur_objpscostdiving.c.

Referenced by SCIPincludeHeurObjpscostdiving().

#define HEUR_FREQ   20

Definition at line 33 of file heur_objpscostdiving.c.

Referenced by SCIPincludeHeurObjpscostdiving().

#define HEUR_FREQOFS   4

Definition at line 34 of file heur_objpscostdiving.c.

Referenced by SCIPincludeHeurObjpscostdiving().

#define HEUR_MAXDEPTH   -1

Definition at line 35 of file heur_objpscostdiving.c.

Referenced by SCIPincludeHeurObjpscostdiving().

#define HEUR_TIMING   SCIP_HEURTIMING_AFTERLPPLUNGE

Definition at line 36 of file heur_objpscostdiving.c.

Referenced by SCIPincludeHeurObjpscostdiving().

#define HEUR_USESSUBSCIP   FALSE

does the heuristic use a secondary SCIP instance?

Definition at line 37 of file heur_objpscostdiving.c.

Referenced by SCIPincludeHeurObjpscostdiving().

#define DEFAULT_MINRELDEPTH   0.0

minimal relative depth to start diving

Definition at line 44 of file heur_objpscostdiving.c.

Referenced by SCIPincludeHeurObjpscostdiving().

#define DEFAULT_MAXRELDEPTH   1.0

maximal relative depth to start diving

Definition at line 45 of file heur_objpscostdiving.c.

Referenced by SCIPincludeHeurObjpscostdiving().

#define DEFAULT_MAXLPITERQUOT   0.01

maximal fraction of diving LP iterations compared to total iteration number

Definition at line 46 of file heur_objpscostdiving.c.

Referenced by SCIPincludeHeurObjpscostdiving().

#define DEFAULT_MAXLPITEROFS   1000

additional number of allowed LP iterations

Definition at line 47 of file heur_objpscostdiving.c.

Referenced by SCIPincludeHeurObjpscostdiving().

#define DEFAULT_MAXSOLS   -1

total number of feasible solutions found up to which heuristic is called (-1: no limit)

Definition at line 48 of file heur_objpscostdiving.c.

Referenced by SCIPincludeHeurObjpscostdiving().

#define DEFAULT_DEPTHFAC   0.5

maximal diving depth: number of binary/integer variables times depthfac

Definition at line 51 of file heur_objpscostdiving.c.

Referenced by SCIPincludeHeurObjpscostdiving().

#define DEFAULT_DEPTHFACNOSOL   2.0

maximal diving depth factor if no feasible solution was found yet

Definition at line 52 of file heur_objpscostdiving.c.

Referenced by SCIPincludeHeurObjpscostdiving().

#define MINLPITER   10000

minimal number of LP iterations allowed in each LP solving call

Definition at line 54 of file heur_objpscostdiving.c.

Referenced by SCIP_DECL_HEUREXEC().

Function Documentation

static void calcPscostQuot ( SCIP *  scip, SCIP_VAR *  var, SCIP_Real  primsol, SCIP_Real  frac, int  rounddir, SCIP_Real *  pscostquot, SCIP_Bool *  roundup  )

static

Parameters

scip	SCIP data structure
var	problem variable
primsol	primal solution of variable
frac	fractionality of variable
rounddir	-1: round down, +1: round up, 0: select due to pseudo cost values
pscostquot	pointer to store pseudo cost quotient
roundup	pointer to store whether the variable should be rounded up

Definition at line 79 of file heur_objpscostdiving.c.

References FALSE, MAX, MIN, NULL, SCIP_DECL_HEURCOPY(), SCIP_Real, SCIPgetVarPseudocostVal(), SCIPvarGetRootSol(), SCIPvarIsBinary(), sqrt(), and TRUE.

Referenced by SCIP_DECL_HEUREXEC().

static SCIP_DECL_HEURCOPY ( heurCopyObjpscostdiving  )

static

copy method for primal heuristic plugins (called when SCIP copies plugins)

Definition at line 140 of file heur_objpscostdiving.c.

References HEUR_NAME, NULL, SCIP_CALL, SCIP_DECL_HEURFREE(), SCIP_OKAY, SCIPheurGetName(), and SCIPincludeHeurObjpscostdiving().

Referenced by calcPscostQuot().

static SCIP_DECL_HEURFREE ( heurFreeObjpscostdiving  )

static

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

Definition at line 154 of file heur_objpscostdiving.c.

References HEUR_NAME, NULL, SCIP_DECL_HEURINIT(), SCIP_OKAY, SCIPfreeMemory, SCIPheurGetData(), SCIPheurGetName(), and SCIPheurSetData().

Referenced by SCIP_DECL_HEURCOPY().

static SCIP_DECL_HEURINIT ( heurInitObjpscostdiving  )

static

initialization method of primal heuristic (called after problem was transformed)

Definition at line 174 of file heur_objpscostdiving.c.

References HEUR_NAME, NULL, SCIP_CALL, SCIP_DECL_HEUREXIT(), SCIP_OKAY, SCIPcreateSol(), SCIPheurGetData(), and SCIPheurGetName().

Referenced by SCIP_DECL_HEURFREE().

static SCIP_DECL_HEUREXIT ( heurExitObjpscostdiving  )

static

deinitialization method of primal heuristic (called before transformed problem is freed)

Definition at line 198 of file heur_objpscostdiving.c.

References HEUR_NAME, NULL, SCIP_CALL, SCIP_DECL_HEUREXEC(), SCIP_OKAY, SCIPfreeSol(), SCIPheurGetData(), and SCIPheurGetName().

Referenced by SCIP_DECL_HEURINIT().

static SCIP_DECL_HEUREXEC ( heurExecObjpscostdiving  )

static

execution method of primal heuristic

Definition at line 218 of file heur_objpscostdiving.c.

References BMSclearMemoryArray, calcPscostQuot(), FALSE, HEUR_NAME, MAX, MIN, MINLPITER, NULL, SCIP_Bool, SCIP_CALL, SCIP_DELAYED, SCIP_DIDNOTFIND, SCIP_DIDNOTRUN, SCIP_FOUNDSOL, SCIP_Longint, SCIP_LPSOLSTAT_OPTIMAL, SCIP_LPSOLSTAT_UNBOUNDEDRAY, SCIP_OKAY, SCIP_Real, SCIPallocBufferArray, SCIPchgVarLbDive(), SCIPchgVarObjDive(), SCIPchgVarUbDive(), SCIPdebugMessage, SCIPendDive(), SCIPfeasCeil(), SCIPfeasFloor(), SCIPfreeBufferArray, SCIPgetCutoffbound(), SCIPgetDepth(), SCIPgetDualbound(), SCIPgetLastDivenode(), SCIPgetLPBranchCands(), SCIPgetLPObjval(), SCIPgetLPSolstat(), SCIPgetMaxDepth(), SCIPgetNBinVars(), SCIPgetNIntVars(), SCIPgetNLPIterations(), SCIPgetNNodeLPIterations(), SCIPgetNNodes(), SCIPgetNSolsFound(), SCIPgetSolOrigObj(), SCIPgetVarLbDive(), SCIPgetVarObjDive(), SCIPgetVarUbDive(), SCIPhasCurrentNodeLP(), SCIPheurGetData(), SCIPheurGetName(), SCIPheurGetNBestSolsFound(), SCIPheurGetNCalls(), SCIPincludeHeurObjpscostdiving(), SCIPisGE(), SCIPisLPSolBasic(), SCIPisStopped(), SCIPlinkLPSol(), SCIProundSol(), SCIPsolveDiveLP(), SCIPstartDive(), SCIPtrySol(), SCIPvarGetName(), SCIPvarGetProbindex(), SCIPvarMayRoundDown(), SCIPvarMayRoundUp(), SCIPwarningMessage(), and TRUE.

Referenced by SCIP_DECL_HEUREXIT().

SCIP_RETCODE SCIPincludeHeurObjpscostdiving

(

SCIP *

scip

)

creates the objpscostdiving heuristic and includes it in SCIP

Parameters

scip	SCIP data structure

Definition at line 601 of file heur_objpscostdiving.c.

References DEFAULT_DEPTHFAC, DEFAULT_DEPTHFACNOSOL, DEFAULT_MAXLPITEROFS, DEFAULT_MAXLPITERQUOT, DEFAULT_MAXRELDEPTH, DEFAULT_MAXSOLS, DEFAULT_MINRELDEPTH, FALSE, HEUR_DESC, HEUR_DISPCHAR, HEUR_FREQ, HEUR_FREQOFS, HEUR_MAXDEPTH, HEUR_NAME, HEUR_PRIORITY, HEUR_TIMING, HEUR_USESSUBSCIP, NULL, SCIP_CALL, SCIP_OKAY, SCIP_REAL_MAX, SCIPaddIntParam(), SCIPaddRealParam(), SCIPallocMemory, SCIPincludeHeurBasic(), SCIPsetHeurCopy(), SCIPsetHeurExit(), SCIPsetHeurFree(), SCIPsetHeurInit(), and TRUE.

Referenced by SCIP_DECL_HEURCOPY(), SCIP_DECL_HEUREXEC(), and SCIPincludeDefaultPlugins().