Scippy

SCIP

Solving Constraint Integer Programs

Macros | Functions
heur_intdiving.c File Reference

Detailed Description

LP diving heuristic that fixes variables with integral LP value.

Author
Tobias Achterberg

Definition in file heur_intdiving.c.

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

Go to the source code of this file.

Macros

#define HEUR_NAME   "intdiving"
 
#define HEUR_DESC   "LP diving heuristic that fixes binary variables with large LP value to one"
 
#define HEUR_DISPCHAR   'n'
 
#define HEUR_PRIORITY   -1003500
 
#define HEUR_FREQ   -1
 
#define HEUR_FREQOFS   9
 
#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   0.05
 
#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 MINLPITER   10000
 

Functions

static SCIP_DECL_HEURCOPY (heurCopyIntdiving)
 
static SCIP_DECL_HEURFREE (heurFreeIntdiving)
 
static SCIP_DECL_HEURINIT (heurInitIntdiving)
 
static SCIP_DECL_HEUREXIT (heurExitIntdiving)
 
static SCIP_DECL_HEUREXEC (heurExecIntdiving)
 
SCIP_RETCODE SCIPincludeHeurIntdiving (SCIP *scip)
 

Macro Definition Documentation

#define HEUR_NAME   "intdiving"

Definition at line 29 of file heur_intdiving.c.

Referenced by SCIPincludeHeurIntdiving().

#define HEUR_DESC   "LP diving heuristic that fixes binary variables with large LP value to one"

Definition at line 30 of file heur_intdiving.c.

Referenced by SCIPincludeHeurIntdiving().

#define HEUR_DISPCHAR   'n'

Definition at line 31 of file heur_intdiving.c.

Referenced by SCIPincludeHeurIntdiving().

#define HEUR_PRIORITY   -1003500

Definition at line 32 of file heur_intdiving.c.

Referenced by SCIPincludeHeurIntdiving().

#define HEUR_FREQ   -1

Definition at line 33 of file heur_intdiving.c.

Referenced by SCIPincludeHeurIntdiving().

#define HEUR_FREQOFS   9

Definition at line 34 of file heur_intdiving.c.

Referenced by SCIPincludeHeurIntdiving().

#define HEUR_MAXDEPTH   -1

Definition at line 35 of file heur_intdiving.c.

Referenced by SCIPincludeHeurIntdiving().

#define HEUR_TIMING   SCIP_HEURTIMING_AFTERLPPLUNGE

Definition at line 36 of file heur_intdiving.c.

Referenced by SCIPincludeHeurIntdiving().

#define HEUR_USESSUBSCIP   FALSE

does the heuristic use a secondary SCIP instance?

Definition at line 37 of file heur_intdiving.c.

Referenced by SCIPincludeHeurIntdiving().

#define DEFAULT_MINRELDEPTH   0.0

minimal relative depth to start diving

Definition at line 44 of file heur_intdiving.c.

Referenced by SCIPincludeHeurIntdiving().

#define DEFAULT_MAXRELDEPTH   1.0

maximal relative depth to start diving

Definition at line 45 of file heur_intdiving.c.

Referenced by SCIPincludeHeurIntdiving().

#define DEFAULT_MAXLPITERQUOT   0.05

maximal fraction of diving LP iterations compared to node LP iterations

Definition at line 46 of file heur_intdiving.c.

Referenced by SCIPincludeHeurIntdiving().

#define DEFAULT_MAXLPITEROFS   1000

additional number of allowed LP iterations

Definition at line 47 of file heur_intdiving.c.

Referenced by SCIPincludeHeurIntdiving().

#define DEFAULT_MAXDIVEUBQUOT   0.8

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

Definition at line 48 of file heur_intdiving.c.

Referenced by SCIPincludeHeurIntdiving().

#define DEFAULT_MAXDIVEAVGQUOT   0.0

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

Definition at line 51 of file heur_intdiving.c.

Referenced by SCIPincludeHeurIntdiving().

#define DEFAULT_MAXDIVEUBQUOTNOSOL   0.1

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

Definition at line 54 of file heur_intdiving.c.

Referenced by SCIPincludeHeurIntdiving().

#define DEFAULT_MAXDIVEAVGQUOTNOSOL   0.0

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

Definition at line 55 of file heur_intdiving.c.

Referenced by SCIPincludeHeurIntdiving().

#define DEFAULT_BACKTRACK   TRUE

use one level of backtracking if infeasibility is encountered?

Definition at line 56 of file heur_intdiving.c.

Referenced by SCIPincludeHeurIntdiving().

#define MINLPITER   10000

minimal number of LP iterations allowed in each LP solving call

Definition at line 58 of file heur_intdiving.c.

Function Documentation

static SCIP_DECL_HEURCOPY ( heurCopyIntdiving  )
static

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

Definition at line 92 of file heur_intdiving.c.

static SCIP_DECL_HEURFREE ( heurFreeIntdiving  )
static

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

Definition at line 106 of file heur_intdiving.c.

static SCIP_DECL_HEURINIT ( heurInitIntdiving  )
static

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

Definition at line 126 of file heur_intdiving.c.

static SCIP_DECL_HEUREXIT ( heurExitIntdiving  )
static

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

Definition at line 150 of file heur_intdiving.c.

static SCIP_DECL_HEUREXEC ( heurExecIntdiving  )
static

execution method of primal heuristic

Definition at line 170 of file heur_intdiving.c.

SCIP_RETCODE SCIPincludeHeurIntdiving ( SCIP *  scip)

creates the intdiving heuristic and includes it in SCIP

Parameters
scipSCIP data structure

Definition at line 647 of file heur_intdiving.c.

References DEFAULT_BACKTRACK, DEFAULT_MAXDIVEAVGQUOT, DEFAULT_MAXDIVEAVGQUOTNOSOL, DEFAULT_MAXDIVEUBQUOT, DEFAULT_MAXDIVEUBQUOTNOSOL, DEFAULT_MAXLPITEROFS, DEFAULT_MAXLPITERQUOT, DEFAULT_MAXRELDEPTH, 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, SCIPaddBoolParam(), SCIPaddIntParam(), SCIPaddRealParam(), SCIPallocMemory, SCIPincludeHeurBasic(), SCIPsetHeurCopy(), SCIPsetHeurExit(), SCIPsetHeurFree(), SCIPsetHeurInit(), and TRUE.

Referenced by SCIPincludeDefaultPlugins().