Scippy

SCIP

Solving Constraint Integer Programs

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Detailed Description

LP diving heuristic that changes variable's objective values using root LP solution as guide.

Author: Kati Wolter

Definition in file heur_rootsoldiving.c.

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

Go to the source code of this file.

Macros
#define	HEUR_NAME "rootsoldiving"

#define	HEUR_DESC "LP diving heuristic that changes variable's objective values using root LP solution as guide"

#define	HEUR_DISPCHAR 'S'

#define	HEUR_PRIORITY -1005000

#define	HEUR_FREQ 20

#define	HEUR_FREQOFS 5

#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

#define	DEFAULT_ALPHA 0.9

Functions
static	SCIP_DECL_HEURCOPY (heurCopyRootsoldiving)

static	SCIP_DECL_HEURFREE (heurFreeRootsoldiving)

static	SCIP_DECL_HEURINIT (heurInitRootsoldiving)

static	SCIP_DECL_HEUREXIT (heurExitRootsoldiving)

static	SCIP_DECL_HEUREXEC (heurExecRootsoldiving)

SCIP_RETCODE	SCIPincludeHeurRootsoldiving (SCIP *scip)

Macro Definition Documentation

#define HEUR_NAME "rootsoldiving"

Definition at line 29 of file heur_rootsoldiving.c.

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

#define HEUR_DESC "LP diving heuristic that changes variable's objective values using root LP solution as guide"

Definition at line 30 of file heur_rootsoldiving.c.

Referenced by SCIPincludeHeurRootsoldiving().

#define HEUR_DISPCHAR 'S'

Definition at line 31 of file heur_rootsoldiving.c.

Referenced by SCIPincludeHeurRootsoldiving().

#define HEUR_PRIORITY -1005000

Definition at line 32 of file heur_rootsoldiving.c.

Referenced by SCIPincludeHeurRootsoldiving().

#define HEUR_FREQ 20

Definition at line 33 of file heur_rootsoldiving.c.

Referenced by SCIPincludeHeurRootsoldiving().

#define HEUR_FREQOFS 5

Definition at line 34 of file heur_rootsoldiving.c.

Referenced by SCIPincludeHeurRootsoldiving().

#define HEUR_MAXDEPTH -1

Definition at line 35 of file heur_rootsoldiving.c.

Referenced by SCIPincludeHeurRootsoldiving().

#define HEUR_TIMING SCIP_HEURTIMING_AFTERLPPLUNGE

Definition at line 36 of file heur_rootsoldiving.c.

Referenced by SCIPincludeHeurRootsoldiving().

#define HEUR_USESSUBSCIP FALSE

does the heuristic use a secondary SCIP instance?

Definition at line 37 of file heur_rootsoldiving.c.

Referenced by SCIPincludeHeurRootsoldiving().

#define DEFAULT_MINRELDEPTH 0.0

minimal relative depth to start diving

Definition at line 44 of file heur_rootsoldiving.c.

Referenced by SCIPincludeHeurRootsoldiving().

#define DEFAULT_MAXRELDEPTH 1.0

maximal relative depth to start diving

Definition at line 45 of file heur_rootsoldiving.c.

Referenced by SCIPincludeHeurRootsoldiving().

#define DEFAULT_MAXLPITERQUOT 0.01

maximal fraction of diving LP iterations compared to node LP iterations

Definition at line 46 of file heur_rootsoldiving.c.

Referenced by SCIPincludeHeurRootsoldiving().

#define DEFAULT_MAXLPITEROFS 1000

additional number of allowed LP iterations

Definition at line 47 of file heur_rootsoldiving.c.

Referenced by SCIPincludeHeurRootsoldiving().

#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_rootsoldiving.c.

Referenced by SCIPincludeHeurRootsoldiving().

#define DEFAULT_DEPTHFAC 0.5

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

Definition at line 50 of file heur_rootsoldiving.c.

Referenced by SCIPincludeHeurRootsoldiving().

#define DEFAULT_DEPTHFACNOSOL 2.0

maximal diving depth factor if no feasible solution was found yet

Definition at line 51 of file heur_rootsoldiving.c.

Referenced by SCIPincludeHeurRootsoldiving().

#define MINLPITER 10000

minimal number of LP iterations allowed in each LP solving call

Definition at line 53 of file heur_rootsoldiving.c.

Referenced by SCIP_DECL_HEUREXEC().

#define DEFAULT_ALPHA 0.9

soft rounding factor to fade out objective coefficients

Definition at line 54 of file heur_rootsoldiving.c.

Referenced by SCIPincludeHeurRootsoldiving().

Function Documentation

static SCIP_DECL_HEURCOPY ( heurCopyRootsoldiving )

static

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

Definition at line 81 of file heur_rootsoldiving.c.

References HEUR_NAME, NULL, SCIP_CALL, SCIP_OKAY, SCIPheurGetName(), and SCIPincludeHeurRootsoldiving().

static SCIP_DECL_HEURFREE ( heurFreeRootsoldiving )

static

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

Definition at line 95 of file heur_rootsoldiving.c.

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

static SCIP_DECL_HEURINIT ( heurInitRootsoldiving )

static

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

Definition at line 115 of file heur_rootsoldiving.c.

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

static SCIP_DECL_HEUREXIT ( heurExitRootsoldiving )

static

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

Definition at line 139 of file heur_rootsoldiving.c.

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

static SCIP_DECL_HEUREXEC ( heurExecRootsoldiving )

static

execution method of primal heuristic

Definition at line 159 of file heur_rootsoldiving.c.

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

SCIP_RETCODE SCIPincludeHeurRootsoldiving ( SCIP * scip )

creates the rootsoldiving heuristic and includes it in SCIP

Parameters

scip	SCIP data structure

Definition at line 572 of file heur_rootsoldiving.c.

References DEFAULT_ALPHA, 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(), and SCIPincludeDefaultPlugins().