Dive sets

Detailed Description

methods for dive sets to control the generic diving algorithm

Functions
const char *	SCIPdivesetGetName (SCIP_DIVESET *diveset)
SCIP_Real	SCIPdivesetGetMinRelDepth (SCIP_DIVESET *diveset)
SCIP_Real	SCIPdivesetGetMaxRelDepth (SCIP_DIVESET *diveset)
SCIP_Longint	SCIPdivesetGetSolSuccess (SCIP_DIVESET *diveset)
int	SCIPdivesetGetNCalls (SCIP_DIVESET *diveset)
int	SCIPdivesetGetNSolutionCalls (SCIP_DIVESET *diveset)
int	SCIPdivesetGetMinDepth (SCIP_DIVESET *diveset)
int	SCIPdivesetGetMaxDepth (SCIP_DIVESET *diveset)
SCIP_Real	SCIPdivesetGetAvgDepth (SCIP_DIVESET *diveset)
int	SCIPdivesetGetMinSolutionDepth (SCIP_DIVESET *diveset)
int	SCIPdivesetGetMaxSolutionDepth (SCIP_DIVESET *diveset)
SCIP_Real	SCIPdivesetGetAvgSolutionDepth (SCIP_DIVESET *diveset)
SCIP_Longint	SCIPdivesetGetNLPIterations (SCIP_DIVESET *diveset)
SCIP_Longint	SCIPdivesetGetNProbingNodes (SCIP_DIVESET *diveset)
SCIP_Longint	SCIPdivesetGetNBacktracks (SCIP_DIVESET *diveset)
SCIP_Longint	SCIPdivesetGetNSols (SCIP_DIVESET *diveset)
SCIP_Real	SCIPdivesetGetMaxLPIterQuot (SCIP_DIVESET *diveset)
int	SCIPdivesetGetMaxLPIterOffset (SCIP_DIVESET *diveset)
SCIP_Real	SCIPdivesetGetUbQuotNoSol (SCIP_DIVESET *diveset)
SCIP_Real	SCIPdivesetGetAvgQuotNoSol (SCIP_DIVESET *diveset)
SCIP_Real	SCIPdivesetGetUbQuot (SCIP_DIVESET *diveset)
SCIP_Real	SCIPdivesetGetAvgQuot (SCIP_DIVESET *diveset)
SCIP_Bool	SCIPdivesetUseBacktrack (SCIP_DIVESET *diveset)
int	SCIPdivesetGetLPSolveFreq (SCIP_DIVESET *diveset)
SCIP_Real	SCIPdivesetGetLPResolveDomChgQuot (SCIP_DIVESET *diveset)
SCIP_Bool	SCIPdivesetUseOnlyLPBranchcands (SCIP_DIVESET *diveset)
SCIP_Bool	SCIPdivesetSupportsType (SCIP_DIVESET *diveset, SCIP_DIVETYPE divetype)
SCIP_RANDNUMGEN *	SCIPdivesetGetRandnumgen (SCIP_DIVESET *diveset)
SCIP_RETCODE	SCIPcreateDiveset (SCIP *scip, SCIP_DIVESET **diveset, SCIP_HEUR *heur, const char *name, SCIP_Real minreldepth, SCIP_Real maxreldepth, SCIP_Real maxlpiterquot, SCIP_Real maxdiveubquot, SCIP_Real maxdiveavgquot, SCIP_Real maxdiveubquotnosol, SCIP_Real maxdiveavgquotnosol, SCIP_Real lpresolvedomchgquot, int lpsolvefreq, int maxlpiterofs, unsigned int initialseed, SCIP_Bool backtrack, SCIP_Bool onlylpbranchcands, SCIP_Bool specificsos1score, SCIP_DECL_DIVESETGETSCORE((*divesetgetscore)))

Function Documentation

SCIPdivesetGetName()

const char* SCIPdivesetGetName

(

SCIP_DIVESET *

diveset

)

get the name of the dive set

Parameters

diveset

diving settings

Definition at line 351 of file heur.c.

References SCIP_Diveset::name.

Referenced by SCIPperformGenericDivingAlgorithm(), SCIPprintHeuristicStatistics(), and solveLP().

SCIPdivesetGetMinRelDepth()

SCIP_Real SCIPdivesetGetMinRelDepth

(

SCIP_DIVESET *

diveset

)

get the minimum relative depth of the diving settings

Parameters

diveset

diving settings

Definition at line 361 of file heur.c.

References SCIP_Diveset::minreldepth.

Referenced by SCIPperformGenericDivingAlgorithm().

SCIPdivesetGetMaxRelDepth()

SCIP_Real SCIPdivesetGetMaxRelDepth

(

SCIP_DIVESET *

diveset

)

get the maximum relative depth of the diving settings

Parameters

diveset

diving settings

Definition at line 369 of file heur.c.

References SCIP_Diveset::maxreldepth.

Referenced by SCIPperformGenericDivingAlgorithm().

SCIPdivesetGetSolSuccess()

SCIP_Longint SCIPdivesetGetSolSuccess

(

SCIP_DIVESET *

diveset

)

get the number of successful runs of the diving settings

Parameters

diveset

diving settings

Definition at line 377 of file heur.c.

References SCIP_Diveset::nbestsolsfound, and SCIP_Diveset::nsolsfound.

Referenced by SCIPperformGenericDivingAlgorithm().

SCIPdivesetGetNCalls()

int SCIPdivesetGetNCalls

(

SCIP_DIVESET *

diveset

)

get the number of calls to this dive set

Parameters

diveset

diving settings

Definition at line 385 of file heur.c.

References SCIP_Diveset::ncalls.

Referenced by SCIPperformGenericDivingAlgorithm(), and SCIPprintHeuristicStatistics().

SCIPdivesetGetNSolutionCalls()

int SCIPdivesetGetNSolutionCalls

(

SCIP_DIVESET *

diveset

)

get the number of calls successfully terminated at a feasible leaf node

Parameters

diveset

diving settings

Definition at line 395 of file heur.c.

References SCIP_Diveset::nsolcalls.

Referenced by SCIPprintHeuristicStatistics().

SCIPdivesetGetMinDepth()

int SCIPdivesetGetMinDepth

(

SCIP_DIVESET *

diveset

)

get the minimum depth reached by this dive set

Parameters

diveset

diving settings

Definition at line 405 of file heur.c.

References SCIP_Diveset::mindepth.

Referenced by SCIPprintHeuristicStatistics().

SCIPdivesetGetMaxDepth()

int SCIPdivesetGetMaxDepth

(

SCIP_DIVESET *

diveset

)

get the maximum depth reached by this dive set

Parameters

diveset

diving settings

Definition at line 415 of file heur.c.

References SCIP_Diveset::maxdepth.

Referenced by SCIPprintHeuristicStatistics().

SCIPdivesetGetAvgDepth()

SCIP_Real SCIPdivesetGetAvgDepth

(

SCIP_DIVESET *

diveset

)

get the average depth this dive set reached during execution

Parameters

diveset

diving settings

Definition at line 425 of file heur.c.

References SCIP_Diveset::ncalls, SCIP_Real, and SCIP_Diveset::totaldepth.

Referenced by SCIPprintHeuristicStatistics().

SCIPdivesetGetMinSolutionDepth()

int SCIPdivesetGetMinSolutionDepth

(

SCIP_DIVESET *

diveset

)

get the minimum depth at which this dive set found a solution

Parameters

diveset

diving settings

Definition at line 435 of file heur.c.

References SCIP_Diveset::minsoldepth.

Referenced by SCIPprintHeuristicStatistics().

SCIPdivesetGetMaxSolutionDepth()

int SCIPdivesetGetMaxSolutionDepth

(

SCIP_DIVESET *

diveset

)

get the maximum depth at which this dive set found a solution

Parameters

diveset

diving settings

Definition at line 445 of file heur.c.

References SCIP_Diveset::maxsoldepth.

Referenced by SCIPprintHeuristicStatistics().

SCIPdivesetGetAvgSolutionDepth()

SCIP_Real SCIPdivesetGetAvgSolutionDepth

(

SCIP_DIVESET *

diveset

)

get the average depth at which this dive set found a solution

Parameters

diveset

diving settings

Definition at line 455 of file heur.c.

References SCIP_Diveset::nsolcalls, SCIP_Real, and SCIP_Diveset::totalsoldepth.

Referenced by SCIPprintHeuristicStatistics().

SCIPdivesetGetNLPIterations()

SCIP_Longint SCIPdivesetGetNLPIterations

(

SCIP_DIVESET *

diveset

)

get the total number of LP iterations used by this dive set

Parameters

diveset

diving settings

Definition at line 465 of file heur.c.

References SCIP_Diveset::nlpiterations.

Referenced by SCIPperformGenericDivingAlgorithm(), SCIPprintHeuristicStatistics(), and solveLP().

SCIPdivesetGetNProbingNodes()

SCIP_Longint SCIPdivesetGetNProbingNodes

(

SCIP_DIVESET *

diveset

)

get the total number of probing nodes used by this dive set

Parameters

diveset

diving settings

Definition at line 475 of file heur.c.

References SCIP_Diveset::totalnnodes.

Referenced by SCIPprintHeuristicStatistics().

SCIPdivesetGetNBacktracks()

SCIP_Longint SCIPdivesetGetNBacktracks

(

SCIP_DIVESET *

diveset

)

get the total number of backtracks performed by this dive set

Parameters

diveset

diving settings

Definition at line 485 of file heur.c.

References SCIP_Diveset::totalnbacktracks.

Referenced by SCIPprintHeuristicStatistics().

SCIPdivesetGetNSols()

SCIP_Longint SCIPdivesetGetNSols

(

SCIP_DIVESET *

diveset

)

get the total number of solutions (leaf and rounded solutions) found by the dive set

Parameters

diveset

diving settings

Definition at line 495 of file heur.c.

References SCIP_Diveset::nsolsfound.

Referenced by SCIPprintHeuristicStatistics().

SCIPdivesetGetMaxLPIterQuot()

SCIP_Real SCIPdivesetGetMaxLPIterQuot

(

SCIP_DIVESET *

diveset

)

get the maximum LP iterations quotient of the diving settings

Parameters

diveset

diving settings

Definition at line 506 of file heur.c.

References SCIP_Diveset::maxlpiterquot.

Referenced by SCIPperformGenericDivingAlgorithm().

SCIPdivesetGetMaxLPIterOffset()

int SCIPdivesetGetMaxLPIterOffset

(

SCIP_DIVESET *

diveset

)

get the maximum LP iterations offset of the diving settings

Parameters

diveset

diving settings

Definition at line 514 of file heur.c.

References SCIP_Diveset::maxlpiterofs.

Referenced by SCIPperformGenericDivingAlgorithm().

SCIPdivesetGetUbQuotNoSol()

SCIP_Real SCIPdivesetGetUbQuotNoSol

(

SCIP_DIVESET *

diveset

)

get the maximum upper bound quotient parameter of the diving settings if no solution is available

Parameters

diveset

diving settings

Definition at line 522 of file heur.c.

References SCIP_Diveset::maxdiveubquotnosol.

Referenced by SCIPperformGenericDivingAlgorithm().

SCIPdivesetGetAvgQuotNoSol()

SCIP_Real SCIPdivesetGetAvgQuotNoSol

(

SCIP_DIVESET *

diveset

)

get the average quotient parameter of the diving settings if no solution is available

Parameters

diveset

diving settings

Definition at line 530 of file heur.c.

References SCIP_Diveset::maxdiveavgquotnosol.

Referenced by SCIPperformGenericDivingAlgorithm().

SCIPdivesetGetUbQuot()

SCIP_Real SCIPdivesetGetUbQuot

(

SCIP_DIVESET *

diveset

)

get the maximum upper bound quotient parameter of the diving settings if an incumbent solution exists

Parameters

diveset

diving settings

Definition at line 537 of file heur.c.

References SCIP_Diveset::maxdiveubquot.

Referenced by SCIPperformGenericDivingAlgorithm().

SCIPdivesetGetAvgQuot()

SCIP_Real SCIPdivesetGetAvgQuot

(

SCIP_DIVESET *

diveset

)

get the average upper bound quotient parameter of the diving settings if an incumbent solution exists

Parameters

diveset

diving settings

Definition at line 545 of file heur.c.

References SCIP_Diveset::maxdiveavgquot.

Referenced by SCIPperformGenericDivingAlgorithm().

SCIPdivesetUseBacktrack()

SCIP_Bool SCIPdivesetUseBacktrack

(

SCIP_DIVESET *

diveset

)

should backtracking be applied?

Parameters

diveset

diving settings

Definition at line 553 of file heur.c.

References SCIP_Diveset::backtrack.

Referenced by SCIPperformGenericDivingAlgorithm().

SCIPdivesetGetLPSolveFreq()

int SCIPdivesetGetLPSolveFreq

(

SCIP_DIVESET *

diveset

)

returns the LP solve frequency for diving LPs (0: dynamically based on number of intermediate domain reductions)

Parameters

diveset

diving settings

Definition at line 561 of file heur.c.

References SCIP_Diveset::lpsolvefreq.

Referenced by SCIPperformGenericDivingAlgorithm().

SCIPdivesetGetLPResolveDomChgQuot()

SCIP_Real SCIPdivesetGetLPResolveDomChgQuot

(

SCIP_DIVESET *

diveset

)

returns the domain reduction quotient for triggering an immediate resolve of the diving LP (0.0: always resolve)

Parameters

diveset

diving settings

Definition at line 582 of file heur.c.

References SCIP_Diveset::lpresolvedomchgquot.

Referenced by SCIPperformGenericDivingAlgorithm().

SCIPdivesetUseOnlyLPBranchcands()

SCIP_Bool SCIPdivesetUseOnlyLPBranchcands

(

SCIP_DIVESET *

diveset

)

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

Parameters

diveset

diving settings

Definition at line 594 of file heur.c.

References SCIP_Diveset::onlylpbranchcands.

Referenced by SCIPperformGenericDivingAlgorithm().

SCIPdivesetSupportsType()

SCIP_Bool SCIPdivesetSupportsType	(	SCIP_DIVESET *	diveset,
		SCIP_DIVETYPE	divetype
	)

returns TRUE if dive set supports diving of the specified type

Parameters

diveset	diving settings
divetype	bit mask that represents the supported dive types by this dive set

Definition at line 604 of file heur.c.

References SCIP_Diveset::divetypemask.

Referenced by getDiveBdChgsSOS1conflictgraph(), and getDiveBdChgsSOS1constraints().

SCIPdivesetGetRandnumgen()

SCIP_RANDNUMGEN* SCIPdivesetGetRandnumgen

(

SCIP_DIVESET *

diveset

)

returns the random number generator of this diveset for tie-breaking

Parameters

diveset

diving settings

Definition at line 571 of file heur.c.

References SCIP_Diveset::randnumgen.

Referenced by SCIP_DECL_DIVESETGETSCORE().

SCIPcreateDiveset()

SCIP_RETCODE SCIPcreateDiveset	(	SCIP *	scip,
		SCIP_DIVESET **	diveset,
		SCIP_HEUR *	heur,
		const char *	name,
		SCIP_Real	minreldepth,
		SCIP_Real	maxreldepth,
		SCIP_Real	maxlpiterquot,
		SCIP_Real	maxdiveubquot,
		SCIP_Real	maxdiveavgquot,
		SCIP_Real	maxdiveubquotnosol,
		SCIP_Real	maxdiveavgquotnosol,
		SCIP_Real	lpresolvedomchgquot,
		int	lpsolvefreq,
		int	maxlpiterofs,
		unsigned int	initialseed,
		SCIP_Bool	backtrack,
		SCIP_Bool	onlylpbranchcands,
		SCIP_Bool	specificsos1score,
		SCIP_DECL_DIVESETGETSCORE((*divesetgetscore))
	)

create a diving set associated with a primal heuristic. The primal heuristic needs to be included before this method can be called. The diveset is installed in the array of divesets of the heuristic and can be retrieved later by accessing SCIPheurGetDivesets()

Returns

SCIP_OKAY is returned if everything worked. otherwise a suitable error code is passed. see SCIP_RETCODE for a complete list of error codes.

Precondition

This method can be called if scip is in one of the following stages:

• SCIP_STAGE_INIT
• SCIP_STAGE_PROBLEM

Parameters

scip	SCIP data structure
diveset	pointer to created diving heuristic settings, or NULL if not needed
heur	primal heuristic to which the diveset belongs
name	name for the diveset, or NULL if the name of the heuristic should be used
minreldepth	minimal relative depth to start diving
maxreldepth	maximal relative depth to start diving
maxlpiterquot	maximal fraction of diving LP iterations compared to node LP iterations
maxdiveubquot	maximal quotient (curlowerbound - lowerbound)/(cutoffbound - lowerbound) where diving is performed (0.0: no limit)
maxdiveavgquot	maximal quotient (curlowerbound - lowerbound)/(avglowerbound - lowerbound) where diving is performed (0.0: no limit)
maxdiveubquotnosol	maximal UBQUOT when no solution was found yet (0.0: no limit)
maxdiveavgquotnosol	maximal AVGQUOT when no solution was found yet (0.0: no limit)
lpresolvedomchgquot	percentage of immediate domain changes during probing to trigger LP resolve
lpsolvefreq	LP solve frequency for (0: only if enough domain reductions are found by propagation)
maxlpiterofs	additional number of allowed LP iterations
initialseed	initial seed for random number generation
backtrack	use one level of backtracking if infeasibility is encountered?
onlylpbranchcands	should only LP branching candidates be considered instead of the slower but more general constraint handler diving variable selection?
specificsos1score	should SOS1 variables be scored by the diving heuristics specific score function; otherwise use the score function of the SOS1 constraint handler

Definition at line 8521 of file scip.c.

References checkStage(), FALSE, Scip::mem, Scip::messagehdlr, SCIP_CALL, SCIP_OKAY, SCIPdivesetCreate(), Scip::set, SCIP_Mem::setmem, and TRUE.

Referenced by SCIPincludeHeurActconsdiving(), SCIPincludeHeurCoefdiving(), SCIPincludeHeurFracdiving(), SCIPincludeHeurGuideddiving(), SCIPincludeHeurLinesearchdiving(), SCIPincludeHeurPscostdiving(), and SCIPincludeHeurVeclendiving().