heur_veclendiving.c File Reference

Detailed Description

LP diving heuristic that rounds variables with long column vectors.

Author

Tobias Achterberg

Definition in file heur_veclendiving.c.

#include "scip/heuristics.h"
#include "scip/heur_veclendiving.h"
#include "scip/pub_heur.h"
#include "scip/pub_lp.h"
#include "scip/pub_message.h"
#include "scip/pub_var.h"
#include "scip/scip_heur.h"
#include "scip/scip_mem.h"
#include "scip/scip_numerics.h"
#include "scip/scip_prob.h"
#include "scip/scip_sol.h"
#include <string.h>

Go to the source code of this file.

Macros
#define	HEUR_NAME   "veclendiving"
#define	HEUR_DESC   "LP diving heuristic that rounds variables with long column vectors"
#define	HEUR_DISPCHAR   SCIP_HEURDISPCHAR_DIVING
#define	HEUR_PRIORITY   -1003100
#define	HEUR_FREQ   10
#define	HEUR_FREQOFS   4
#define	HEUR_MAXDEPTH   -1
#define	HEUR_TIMING   SCIP_HEURTIMING_AFTERLPPLUNGE
#define	HEUR_USESSUBSCIP   FALSE
#define	DIVESET_DIVETYPES   SCIP_DIVETYPE_INTEGRALITY
#define	DIVESET_ISPUBLIC   TRUE
#define	DEFAULT_MINRELDEPTH   0.0
#define	DEFAULT_MAXRELDEPTH   1.0
#define	DEFAULT_MAXLPITERQUOT   0.05
#define	DEFAULT_MAXLPITEROFS   1000
#define	DEFAULT_MAXDIVEUBQUOT   0.8
#define	DEFAULT_MAXDIVEAVGQUOT   0.0
#define	DEFAULT_MAXDIVEUBQUOTNOSOL   0.1
#define	DEFAULT_MAXDIVEAVGQUOTNOSOL   0.0
#define	DEFAULT_BACKTRACK   TRUE
#define	DEFAULT_LPRESOLVEDOMCHGQUOT   0.15
#define	DEFAULT_LPSOLVEFREQ   0
#define	DEFAULT_ONLYLPBRANCHCANDS   FALSE
#define	DEFAULT_RANDSEED   113
#define	divesetAvailableVeclendiving   NULL

Functions
static	SCIP_DECL_HEURCOPY (heurCopyVeclendiving)
static	assert (heur !=NULL)
	assert (strcmp(SCIPheurGetName(heur), HEUR_NAME)==0)
	assert (scip !=NULL)
	assert (heurdata !=NULL)
	SCIPfreeBlockMemory (scip, &heurdata)
	SCIPheurSetData (heur, NULL)
	SCIPcreateSol (scip, &heurdata->sol, heur))
	SCIPfreeSol (scip, &heurdata->sol))
	assert (SCIPheurGetNDivesets(heur) > 0)
	assert (SCIPheurGetDivesets(heur) !=NULL)
	assert (diveset !=NULL)
	if (SCIPgetNBinVars(scip)+SCIPgetNIntVars(scip)==0)
SCIP_RETCODE	SCIPincludeHeurVeclendiving (SCIP *scip)

Variables
	heurdata = SCIPheurGetData(heur)
return	SCIP_OKAY
static SCIP_DIVESET *	diveset
*	result = SCIP_DIDNOTRUN

Macro Definition Documentation

HEUR_NAME

#define HEUR_NAME   "veclendiving"

Definition at line 46 of file heur_veclendiving.c.

HEUR_DESC

#define HEUR_DESC   "LP diving heuristic that rounds variables with long column vectors"

Definition at line 47 of file heur_veclendiving.c.

HEUR_DISPCHAR

#define HEUR_DISPCHAR   SCIP_HEURDISPCHAR_DIVING

Definition at line 48 of file heur_veclendiving.c.

HEUR_PRIORITY

#define HEUR_PRIORITY   -1003100

Definition at line 49 of file heur_veclendiving.c.

HEUR_FREQ

#define HEUR_FREQ   10

Definition at line 50 of file heur_veclendiving.c.

HEUR_FREQOFS

#define HEUR_FREQOFS   4

Definition at line 51 of file heur_veclendiving.c.

HEUR_MAXDEPTH

#define HEUR_MAXDEPTH   -1

Definition at line 52 of file heur_veclendiving.c.

HEUR_TIMING

#define HEUR_TIMING   SCIP_HEURTIMING_AFTERLPPLUNGE

Definition at line 53 of file heur_veclendiving.c.

HEUR_USESSUBSCIP

#define HEUR_USESSUBSCIP   FALSE

does the heuristic use a secondary SCIP instance?

Definition at line 54 of file heur_veclendiving.c.

DIVESET_DIVETYPES

#define DIVESET_DIVETYPES   SCIP_DIVETYPE_INTEGRALITY

bit mask that represents all supported dive types

Definition at line 55 of file heur_veclendiving.c.

DIVESET_ISPUBLIC

#define DIVESET_ISPUBLIC   TRUE

is this dive set publicly available (ie., can be used by other primal heuristics?)

Definition at line 56 of file heur_veclendiving.c.

DEFAULT_MINRELDEPTH

#define DEFAULT_MINRELDEPTH   0.0

minimal relative depth to start diving

Definition at line 63 of file heur_veclendiving.c.

DEFAULT_MAXRELDEPTH

#define DEFAULT_MAXRELDEPTH   1.0

maximal relative depth to start diving

Definition at line 64 of file heur_veclendiving.c.

DEFAULT_MAXLPITERQUOT

#define DEFAULT_MAXLPITERQUOT   0.05

maximal fraction of diving LP iterations compared to node LP iterations

Definition at line 65 of file heur_veclendiving.c.

DEFAULT_MAXLPITEROFS

#define DEFAULT_MAXLPITEROFS   1000

additional number of allowed LP iterations

Definition at line 66 of file heur_veclendiving.c.

DEFAULT_MAXDIVEUBQUOT

#define DEFAULT_MAXDIVEUBQUOT   0.8

maximal quotient (curlowerbound - lowerbound)/(cutoffbound - lowerbound) where diving is performed (0.0: no limit)

Definition at line 67 of file heur_veclendiving.c.

DEFAULT_MAXDIVEAVGQUOT

#define DEFAULT_MAXDIVEAVGQUOT   0.0

maximal quotient (curlowerbound - lowerbound)/(avglowerbound - lowerbound) where diving is performed (0.0: no limit)

Definition at line 69 of file heur_veclendiving.c.

DEFAULT_MAXDIVEUBQUOTNOSOL

#define DEFAULT_MAXDIVEUBQUOTNOSOL   0.1

maximal UBQUOT when no solution was found yet (0.0: no limit)

Definition at line 71 of file heur_veclendiving.c.

DEFAULT_MAXDIVEAVGQUOTNOSOL

#define DEFAULT_MAXDIVEAVGQUOTNOSOL   0.0

maximal AVGQUOT when no solution was found yet (0.0: no limit)

Definition at line 72 of file heur_veclendiving.c.

DEFAULT_BACKTRACK

#define DEFAULT_BACKTRACK   TRUE

use one level of backtracking if infeasibility is encountered?

Definition at line 73 of file heur_veclendiving.c.

DEFAULT_LPRESOLVEDOMCHGQUOT

#define DEFAULT_LPRESOLVEDOMCHGQUOT   0.15

percentage of immediate domain changes during probing to trigger LP resolve

Definition at line 74 of file heur_veclendiving.c.

DEFAULT_LPSOLVEFREQ

#define DEFAULT_LPSOLVEFREQ   0

LP solve frequency for diving heuristics

Definition at line 75 of file heur_veclendiving.c.

DEFAULT_ONLYLPBRANCHCANDS

#define DEFAULT_ONLYLPBRANCHCANDS   FALSE

should only LP branching candidates be considered instead of the slower but more general constraint handler diving variable selection?

Definition at line 76 of file heur_veclendiving.c.

DEFAULT_RANDSEED

#define DEFAULT_RANDSEED   113

initial seed for random number generation

Definition at line 78 of file heur_veclendiving.c.

divesetAvailableVeclendiving

#define divesetAvailableVeclendiving   NULL

Definition at line 219 of file heur_veclendiving.c.

Referenced by SCIPincludeHeurVeclendiving().

Function Documentation

SCIP_DECL_HEURCOPY()

SCIP_DECL_HEURCOPY ( heurCopyVeclendiving )

static

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

Definition at line 97 of file heur_veclendiving.c.

References assert(), HEUR_NAME, NULL, SCIP_CALL, SCIP_OKAY, SCIPheurGetName(), and SCIPincludeHeurVeclendiving().

assert() [1/7]

assert

(

heur !

= NULL

)

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

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

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

References NULL.

assert() [2/7]

assert

(

strcmp(SCIPheurGetName(heur), HEUR_NAME)

= =0

)

References HEUR_NAME.

assert() [3/7]

assert

(

scip !

= NULL

)

References NULL.

assert() [4/7]

assert

(

heurdata !

= NULL

)

References heurdata, and NULL.

SCIPfreeBlockMemory()

SCIPfreeBlockMemory	(	scip	,
		&	heurdata )

References heurdata.

SCIPheurSetData()

SCIPheurSetData	(	heur	,
		NULL	)

References NULL.

SCIPcreateSol()

SCIPcreateSol	(	scip	,
		&heurdata->	sol,
		heur	)

References heurdata, and SCIP_OKAY.

SCIPfreeSol()

SCIPfreeSol	(	scip	,
		&heurdata->	sol )

References heurdata, and SCIP_OKAY.

assert() [5/7]

assert	(	SCIPheurGetNDivesets(heur)	,
		0	)

assert() [6/7]

assert

(

SCIPheurGetDivesets(heur) !

= NULL

)

References diveset, and NULL.

assert() [7/7]

assert

(

diveset !

= NULL

)

References diveset, and NULL.

if()

if

(

SCIPgetNBinVars(scip)+SCIPgetNIntVars(scip)

= = 0

)

calculate score and preferred rounding direction for the candidate variable

Definition at line 186 of file heur_veclendiving.c.

References diveset, heurdata, result, SCIP_DIVECONTEXT_SINGLE, and SCIP_OKAY.

Variable Documentation

heurdata

heurdata = SCIPheurGetData(heur)

Definition at line 120 of file heur_veclendiving.c.

SCIP_OKAY

return SCIP_OKAY

Definition at line 126 of file heur_veclendiving.c.

diveset

diveset

Initial value:

{  
   SCIP_HEURDATA* heurdata

execution method of primal heuristic

Definition at line 175 of file heur_veclendiving.c.

result

* result = SCIP_DIDNOTRUN

Definition at line 183 of file heur_veclendiving.c.