Scippy

SCIP

Solving Constraint Integer Programs

Detailed Description

OFINS - Objective Function Induced Neighborhood Search - a primal heuristic for reoptimization.

Author
Jakob Witzig

Definition in file heur_ofins.c.

#include "blockmemshell/memory.h"
#include "scip/heuristics.h"
#include "scip/heur_ofins.h"
#include "scip/pub_event.h"
#include "scip/pub_heur.h"
#include "scip/pub_message.h"
#include "scip/pub_misc.h"
#include "scip/pub_sol.h"
#include "scip/pub_var.h"
#include "scip/scip_branch.h"
#include "scip/scip_copy.h"
#include "scip/scip_event.h"
#include "scip/scip_general.h"
#include "scip/scip_heur.h"
#include "scip/scip_mem.h"
#include "scip/scip_message.h"
#include "scip/scip_nodesel.h"
#include "scip/scip_numerics.h"
#include "scip/scip_param.h"
#include "scip/scip_prob.h"
#include "scip/scip_sol.h"
#include "scip/scip_solve.h"
#include "scip/scip_solvingstats.h"
#include "scip/scip_timing.h"
#include <string.h>

Go to the source code of this file.

Macros

#define HEUR_NAME   "ofins"
 
#define HEUR_DESC   "primal heuristic for reoptimization, objective function induced neighborhood search"
 
#define HEUR_DISPCHAR   SCIP_HEURDISPCHAR_LNS
 
#define HEUR_PRIORITY   60000
 
#define HEUR_FREQ   0
 
#define HEUR_FREQOFS   0
 
#define HEUR_MAXDEPTH   0
 
#define HEUR_TIMING   SCIP_HEURTIMING_BEFORENODE
 
#define HEUR_USESSUBSCIP   TRUE
 
#define DEFAULT_MAXNODES   5000LL
 
#define DEFAULT_MAXCHGRATE   0.50
 
#define DEFAULT_COPYCUTS   TRUE
 
#define DEFAULT_MAXCHANGE   0.04
 
#define DEFAULT_MINIMPROVE   0.01
 
#define DEFAULT_ADDALLSOLS   FALSE
 
#define DEFAULT_MINNODES   50LL
 
#define DEFAULT_NODESOFS   500LL
 
#define DEFAULT_NODESQUOT   0.1
 
#define DEFAULT_LPLIMFAC   2.0
 
#define EVENTHDLR_NAME   "Ofins"
 
#define EVENTHDLR_DESC   "LP event handler for " HEUR_NAME " heuristic"
 

Functions

static SCIP_DECL_EVENTEXEC (eventExecOfins)
 
static SCIP_RETCODE setupAndSolve (SCIP *scip, SCIP *subscip, SCIP_HEUR *heur, SCIP_HEURDATA *heurdata, SCIP_RESULT *result, SCIP_Longint nstallnodes, SCIP_Bool *chgcoeffs)
 
static SCIP_RETCODE applyOfins (SCIP *scip, SCIP_HEUR *heur, SCIP_HEURDATA *heurdata, SCIP_RESULT *result, SCIP_Longint nstallnodes, SCIP_Bool *chgcoeffs)
 
static SCIP_DECL_HEURCOPY (heurCopyOfins)
 
static SCIP_DECL_HEURFREE (heurFreeOfins)
 
static SCIP_DECL_HEUREXEC (heurExecOfins)
 
SCIP_RETCODE SCIPincludeHeurOfins (SCIP *scip)
 

Macro Definition Documentation

◆ HEUR_NAME

#define HEUR_NAME   "ofins"

Definition at line 59 of file heur_ofins.c.

Referenced by SCIP_DECL_HEURCOPY(), SCIPincludeHeurOfins(), and setupAndSolve().

◆ HEUR_DESC

#define HEUR_DESC   "primal heuristic for reoptimization, objective function induced neighborhood search"

Definition at line 60 of file heur_ofins.c.

Referenced by SCIPincludeHeurOfins().

◆ HEUR_DISPCHAR

#define HEUR_DISPCHAR   SCIP_HEURDISPCHAR_LNS

Definition at line 61 of file heur_ofins.c.

Referenced by SCIPincludeHeurOfins().

◆ HEUR_PRIORITY

#define HEUR_PRIORITY   60000

Definition at line 62 of file heur_ofins.c.

Referenced by SCIPincludeHeurOfins().

◆ HEUR_FREQ

#define HEUR_FREQ   0

Definition at line 63 of file heur_ofins.c.

Referenced by SCIPincludeHeurOfins().

◆ HEUR_FREQOFS

#define HEUR_FREQOFS   0

Definition at line 64 of file heur_ofins.c.

Referenced by SCIPincludeHeurOfins().

◆ HEUR_MAXDEPTH

#define HEUR_MAXDEPTH   0

Definition at line 65 of file heur_ofins.c.

Referenced by SCIPincludeHeurOfins().

◆ HEUR_TIMING

#define HEUR_TIMING   SCIP_HEURTIMING_BEFORENODE

Definition at line 66 of file heur_ofins.c.

Referenced by SCIPincludeHeurOfins().

◆ HEUR_USESSUBSCIP

#define HEUR_USESSUBSCIP   TRUE

does the heuristic use a secondary SCIP instance?

Definition at line 67 of file heur_ofins.c.

Referenced by SCIPincludeHeurOfins().

◆ DEFAULT_MAXNODES

#define DEFAULT_MAXNODES   5000LL

maximum number of nodes to regard in the subproblem

Definition at line 70 of file heur_ofins.c.

Referenced by SCIPincludeHeurOfins().

◆ DEFAULT_MAXCHGRATE

#define DEFAULT_MAXCHGRATE   0.50

maximum percentage of changed objective coefficients

Definition at line 71 of file heur_ofins.c.

Referenced by SCIPincludeHeurOfins().

◆ DEFAULT_COPYCUTS

#define DEFAULT_COPYCUTS   TRUE

if DEFAULT_USELPROWS is FALSE, then should all active cuts from the cutpool of the original scip be copied to constraints of the subscip

Definition at line 72 of file heur_ofins.c.

Referenced by SCIPincludeHeurOfins().

◆ DEFAULT_MAXCHANGE

#define DEFAULT_MAXCHANGE   0.04

maximal rate of change per coefficient to get fixed

Definition at line 75 of file heur_ofins.c.

Referenced by SCIPincludeHeurOfins().

◆ DEFAULT_MINIMPROVE

#define DEFAULT_MINIMPROVE   0.01

factor by which OFINS should at least improve the incumbent

Definition at line 76 of file heur_ofins.c.

Referenced by SCIPincludeHeurOfins().

◆ DEFAULT_ADDALLSOLS

#define DEFAULT_ADDALLSOLS   FALSE

should all subproblem solutions be added to the original SCIP?

Definition at line 77 of file heur_ofins.c.

Referenced by SCIPincludeHeurOfins().

◆ DEFAULT_MINNODES

#define DEFAULT_MINNODES   50LL

minimum number of nodes to regard in the subproblem

Definition at line 78 of file heur_ofins.c.

Referenced by SCIPincludeHeurOfins().

◆ DEFAULT_NODESOFS

#define DEFAULT_NODESOFS   500LL

number of nodes added to the contingent of the total nodes

Definition at line 79 of file heur_ofins.c.

Referenced by SCIPincludeHeurOfins().

◆ DEFAULT_NODESQUOT

#define DEFAULT_NODESQUOT   0.1

subproblem nodes in relation to nodes of the original problem

Definition at line 80 of file heur_ofins.c.

Referenced by SCIPincludeHeurOfins().

◆ DEFAULT_LPLIMFAC

#define DEFAULT_LPLIMFAC   2.0

factor by which the limit on the number of LP depends on the node limit

Definition at line 81 of file heur_ofins.c.

Referenced by SCIPincludeHeurOfins().

◆ EVENTHDLR_NAME

#define EVENTHDLR_NAME   "Ofins"

Definition at line 84 of file heur_ofins.c.

Referenced by SCIP_DECL_EVENTEXEC(), and setupAndSolve().

◆ EVENTHDLR_DESC

#define EVENTHDLR_DESC   "LP event handler for " HEUR_NAME " heuristic"

Definition at line 85 of file heur_ofins.c.

Referenced by setupAndSolve().

Function Documentation

◆ SCIP_DECL_EVENTEXEC()

static SCIP_DECL_EVENTEXEC ( eventExecOfins  )
static

◆ setupAndSolve()

static SCIP_RETCODE setupAndSolve ( SCIP scip,
SCIP subscip,
SCIP_HEUR heur,
SCIP_HEURDATA heurdata,
SCIP_RESULT result,
SCIP_Longint  nstallnodes,
SCIP_Bool chgcoeffs 
)
static
Parameters
sciporiginal SCIP data structure
subscipsub-SCIP data structure
heurheuristic data structure
heurdataeuristic's private data structure
resultresult data structure
nstallnodesnumber of stalling nodes for the subproblem
chgcoeffsarray of changed coefficients

Definition at line 136 of file heur_ofins.c.

References applyOfins(), EVENTHDLR_DESC, EVENTHDLR_NAME, FALSE, HEUR_NAME, NULL, SCIP_Bool, SCIP_CALL, SCIP_CALL_ABORT, SCIP_EVENTTYPE_LPSOLVED, SCIP_FOUNDSOL, SCIP_OKAY, SCIP_PARAMSETTING_FAST, SCIP_PARAMSETTING_OFF, SCIP_PLUGINNOTFOUND, SCIP_Real, SCIP_STATUS_INFEASIBLE, SCIP_STATUS_INFORUNBD, SCIP_STATUS_UNBOUNDED, SCIP_UNBOUNDED, SCIPABORT, SCIPallocBufferArray, SCIPblkmem(), SCIPcatchEvent(), SCIPcopyLargeNeighborhoodSearch(), SCIPcopyLimits(), SCIPcreateSol(), SCIPdebug, SCIPdebugMsg, SCIPdropEvent(), SCIPerrorMessage, SCIPfindBranchrule(), SCIPfindNodesel(), SCIPfreeBufferArray, SCIPfreeBufferArrayNull, SCIPfreeSol(), SCIPgetBestSol(), SCIPgetNBinVars(), SCIPgetNConss(), SCIPgetNImplVars(), SCIPgetNIntVars(), SCIPgetNNodes(), SCIPgetNSols(), SCIPgetNVars(), SCIPgetPrimalbound(), SCIPgetPrimalRayVal(), SCIPgetReoptLastOptSol(), SCIPgetSols(), SCIPgetSolVal(), SCIPgetSolvingTime(), SCIPgetStatus(), SCIPgetUpperbound(), SCIPgetVars(), SCIPhashmapCreate(), SCIPhashmapFree(), SCIPhashmapGetImage(), SCIPhasPrimalRay(), SCIPincludeEventhdlrBasic(), SCIPinfinity(), SCIPisParamFixed(), SCIPpresolve(), SCIPprintRay(), SCIPprintStatistics(), SCIPsetBoolParam(), SCIPsetIntParam(), SCIPsetLongintParam(), SCIPsetObjlimit(), SCIPsetPresolving(), SCIPsetSeparating(), SCIPsetSolVal(), SCIPsetSubscipsOff(), SCIPsolGetNodenum(), SCIPsolve(), SCIPstatisticPrintf, SCIPtransformProb(), SCIPtranslateSubSol(), SCIPtrySolFree(), SCIPupdatePrimalRay(), SCIPwarningMessage(), and TRUE.

Referenced by applyOfins(), and SCIP_DECL_EVENTEXEC().

◆ applyOfins()

static SCIP_RETCODE applyOfins ( SCIP scip,
SCIP_HEUR heur,
SCIP_HEURDATA heurdata,
SCIP_RESULT result,
SCIP_Longint  nstallnodes,
SCIP_Bool chgcoeffs 
)
static

main procedure of the OFINS heuristic, creates and solves a sub-SCIP

Parameters
sciporiginal SCIP data structure
heurheuristic data structure
heurdataeuristic's private data structure
resultresult data structure
nstallnodesnumber of stalling nodes for the subproblem
chgcoeffsarray of changed coefficients

Definition at line 390 of file heur_ofins.c.

References NULL, SCIP_Bool, SCIP_CALL, SCIP_DECL_HEURCOPY(), SCIP_DIDNOTFIND, SCIP_DIDNOTRUN, SCIP_OKAY, SCIPcheckCopyLimits(), SCIPcreate(), SCIPfree(), SCIPgetReoptLastOptSol(), and setupAndSolve().

Referenced by SCIP_DECL_HEUREXEC(), and setupAndSolve().

◆ SCIP_DECL_HEURCOPY()

static SCIP_DECL_HEURCOPY ( heurCopyOfins  )
static

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

Definition at line 444 of file heur_ofins.c.

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

Referenced by applyOfins().

◆ SCIP_DECL_HEURFREE()

static SCIP_DECL_HEURFREE ( heurFreeOfins  )
static

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

Definition at line 458 of file heur_ofins.c.

References NULL, SCIP_DECL_HEUREXEC(), SCIP_OKAY, SCIPfreeBlockMemory, SCIPheurGetData(), and SCIPheurSetData().

Referenced by SCIP_DECL_HEURCOPY().

◆ SCIP_DECL_HEUREXEC()