Detailed Description

internal methods for branching and inference history

Author: Tobias Achterberg; Timo Berthold

Definition in file history.h.

#include "scip/def.h"
#include "blockmemshell/memory.h"
#include "scip/type_retcode.h"
#include "scip/type_set.h"
#include "scip/type_history.h"

Go to the source code of this file.

Functions
SCIP_RETCODE	SCIPhistoryCreate (SCIP_HISTORY *history, BMS_BLKMEM blkmem)

void	SCIPhistoryFree (SCIP_HISTORY *history, BMS_BLKMEM blkmem)

void	SCIPhistoryReset (SCIP_HISTORY *history)

void	SCIPhistoryUnite (SCIP_HISTORY history, SCIP_HISTORY addhistory, SCIP_Bool switcheddirs)

void	SCIPhistoryUpdatePseudocost (SCIP_HISTORY history, SCIP_SET set, SCIP_Real solvaldelta, SCIP_Real objdelta, SCIP_Real weight)

SCIP_RETCODE	SCIPvaluehistoryCreate (SCIP_VALUEHISTORY *valuehistory, BMS_BLKMEM blkmem)

void	SCIPvaluehistoryFree (SCIP_VALUEHISTORY *valuehistory, BMS_BLKMEM blkmem)

SCIP_RETCODE	SCIPvaluehistoryFind (SCIP_VALUEHISTORY valuehistory, BMS_BLKMEM blkmem, SCIP_SET set, SCIP_Real value, SCIP_HISTORY *history)

void	SCIPvaluehistoryScaleVSIDS (SCIP_VALUEHISTORY *valuehistory, SCIP_Real scalar)

SCIP_BRANCHDIR	SCIPbranchdirOpposite (SCIP_BRANCHDIR dir)

SCIP_Real	SCIPhistoryGetPseudocost (SCIP_HISTORY *history, SCIP_Real solvaldelta)

SCIP_Real	SCIPhistoryGetPseudocostVariance (SCIP_HISTORY *history, SCIP_BRANCHDIR direction)

SCIP_Real	SCIPhistoryGetPseudocostCount (SCIP_HISTORY *history, SCIP_BRANCHDIR dir)

SCIP_Bool	SCIPhistoryIsPseudocostEmpty (SCIP_HISTORY *history, SCIP_BRANCHDIR dir)

void	SCIPhistoryIncVSIDS (SCIP_HISTORY *history, SCIP_BRANCHDIR dir, SCIP_Real weight)

void	SCIPhistoryScaleVSIDS (SCIP_HISTORY *history, SCIP_Real scalar)

void	SCIPhistoryIncNActiveConflicts (SCIP_HISTORY *history, SCIP_BRANCHDIR dir, SCIP_Real length)

SCIP_Longint	SCIPhistoryGetNActiveConflicts (SCIP_HISTORY *history, SCIP_BRANCHDIR dir)

void	SCIPhistoryIncNBranchings (SCIP_HISTORY *history, SCIP_BRANCHDIR dir, int depth)

void	SCIPhistoryIncInferenceSum (SCIP_HISTORY *history, SCIP_BRANCHDIR dir, SCIP_Real weight)

void	SCIPhistoryIncCutoffSum (SCIP_HISTORY *history, SCIP_BRANCHDIR dir, SCIP_Real weight)

SCIP_Longint	SCIPhistoryGetNBranchings (SCIP_HISTORY *history, SCIP_BRANCHDIR dir)

SCIP_Real	SCIPhistoryGetAvgInferences (SCIP_HISTORY *history, SCIP_BRANCHDIR dir)

SCIP_Real	SCIPhistoryGetAvgCutoffs (SCIP_HISTORY *history, SCIP_BRANCHDIR dir)

SCIP_Real	SCIPhistoryGetAvgBranchdepth (SCIP_HISTORY *history, SCIP_BRANCHDIR dir)

SCIP_Bool	SCIPhistoryIsRatioValid (SCIP_HISTORY *history)

SCIP_Real	SCIPhistoryGetLastRatio (SCIP_HISTORY *history)

SCIP_Real	SCIPhistoryGetLastBalance (SCIP_HISTORY *history)

void	SCIPhistorySetRatioHistory (SCIP_HISTORY *history, SCIP_Bool valid, SCIP_Real ratio, SCIP_Real balance)

Function Documentation

◆ SCIPhistoryCreate()

SCIP_RETCODE SCIPhistoryCreate	(	SCIP_HISTORY **	history,
		BMS_BLKMEM *	blkmem
	)

creates an empty history entry

Parameters

history	pointer to store branching and inference history
blkmem	block memory

Definition at line 51 of file history.c.

References BMSallocBlockMemory, NULL, SCIP_ALLOC, SCIP_OKAY, and SCIPhistoryReset().

Referenced by SCIPreoptUpdateVarHistory(), SCIPstatCreate(), SCIPvaluehistoryFind(), and varCreate().

◆ SCIPhistoryFree()

void SCIPhistoryFree	(	SCIP_HISTORY **	history,
		BMS_BLKMEM *	blkmem
	)

frees a history entry

Parameters

history	pointer to branching and inference history
blkmem	block memory

Definition at line 66 of file history.c.

References BMSfreeBlockMemory, and NULL.

Referenced by SCIPreoptFree(), SCIPstatFree(), SCIPvaluehistoryFree(), and varFree().

◆ SCIPhistoryReset()

void SCIPhistoryReset ( SCIP_HISTORY * history )

resets history entry to zero

Parameters

history branching and inference history

Definition at line 78 of file history.c.

References SCIP_History::balance, SCIP_History::branchdepthsum, SCIP_History::conflengthsum, SCIP_History::cutoffsum, FALSE, SCIP_History::inferencesum, SCIP_History::nactiveconflicts, SCIP_History::nbranchings, NULL, SCIP_History::pscostcount, SCIP_History::pscostvariance, SCIP_History::pscostweightedmean, SCIP_History::ratio, SCIP_History::ratiovalid, and SCIP_History::vsids.

Referenced by SCIPhistoryCreate(), SCIPreoptUpdateVarHistory(), SCIPstatReset(), SCIPstatResetCurrentRun(), SCIPvarAggregate(), SCIPvarFix(), and SCIPvarInitSolve().

◆ SCIPhistoryUnite()

void SCIPhistoryUnite	(	SCIP_HISTORY *	history,
		SCIP_HISTORY *	addhistory,
		SCIP_Bool	switcheddirs
	)

unites two history entries by adding the values of the second one to the first one

Parameters

history	branching and inference history
addhistory	history values to add to history
switcheddirs	should the history entries be united with switched directories

Definition at line 110 of file history.c.

References SCIP_History::branchdepthsum, SCIP_History::conflengthsum, SCIP_History::cutoffsum, SCIP_History::inferencesum, MAX, SCIP_History::nactiveconflicts, SCIP_History::nbranchings, NULL, SCIP_History::pscostcount, SCIP_History::pscostvariance, SCIP_History::pscostweightedmean, SCIP_Real, and SCIP_History::vsids.

Referenced by SCIPreoptUpdateVarHistory(), SCIPvarAggregate(), SCIPvarMergeHistories(), SCIPvarSetHistory(), and SCIPvarTransform().

◆ SCIPhistoryUpdatePseudocost()

void SCIPhistoryUpdatePseudocost	(	SCIP_HISTORY *	history,
		SCIP_SET *	set,
		SCIP_Real	solvaldelta,
		SCIP_Real	objdelta,
		SCIP_Real	weight
	)

updates the pseudo costs for a change of "solvaldelta" in the variable's LP solution value and a change of "objdelta" in the LP's objective value

Parameters

history	branching and inference history
set	global SCIP settings
solvaldelta	difference of variable's new LP value - old LP value
objdelta	difference of new LP's objective value - old LP's objective value
weight	weight of this update in pseudo cost sum (added to pscostcount)

Definition at line 171 of file history.c.

References eps, MAX, NULL, SCIP_History::pscostcount, SCIP_History::pscostvariance, SCIP_History::pscostweightedmean, REALABS, SCIP_Real, SCIPsetDebugMsg, SCIPsetIsInfinity(), SCIPsetIsNegative(), SCIPsetIsPositive(), SCIPsetPseudocostdelta(), and SCIPsetPseudocosteps().

Referenced by SCIPvarUpdatePseudocost().

◆ SCIPbranchdirOpposite()

SCIP_BRANCHDIR SCIPbranchdirOpposite ( SCIP_BRANCHDIR dir )

returns the opposite direction of the given branching direction

Parameters

dir	branching direction

Definition at line 430 of file history.c.

References SCIP_BRANCHDIR_AUTO, SCIP_BRANCHDIR_DOWNWARDS, and SCIP_BRANCHDIR_UPWARDS.

◆ SCIPhistoryGetPseudocost()

SCIP_Real SCIPhistoryGetPseudocost	(	SCIP_HISTORY *	history,
		SCIP_Real	solvaldelta
	)

returns the expected dual gain for moving the corresponding variable by "solvaldelta"

Parameters

history	branching and inference history
solvaldelta	difference of variable's new LP value - old LP value

Definition at line 439 of file history.c.

References NULL, SCIP_History::pscostcount, and SCIP_History::pscostweightedmean.

Referenced by SCIPgetAvgPseudocost(), SCIPgetAvgPseudocostCurrentRun(), SCIPgetAvgPseudocostScore(), SCIPgetAvgPseudocostScoreCurrentRun(), SCIPprintBranchingStatistics(), SCIPvarGetPseudocost(), and SCIPvarGetPseudocostCurrentRun().

◆ SCIPhistoryGetPseudocostVariance()

SCIP_Real SCIPhistoryGetPseudocostVariance	(	SCIP_HISTORY *	history,
		SCIP_BRANCHDIR	direction
	)

returns the variance of pseudo costs about the mean.

Parameters

history	branching and inference history
direction	direction of variable: 1 for upwards history, 0 for downwards history

Definition at line 453 of file history.c.

References NULL, SCIP_History::pscostcount, SCIP_History::pscostvariance, SCIP_BRANCHDIR_DOWNWARDS, SCIP_BRANCHDIR_UPWARDS, and SCIP_Real.

Referenced by SCIPgetPseudocostVariance(), SCIPprintBranchingStatistics(), and SCIPvarGetPseudocostVariance().

◆ SCIPhistoryGetPseudocostCount()

SCIP_Real SCIPhistoryGetPseudocostCount	(	SCIP_HISTORY *	history,
		SCIP_BRANCHDIR	dir
	)

returns the (possible fractional) number of (partial) pseudo cost updates performed on this pseudo cost entry in the given branching direction

Parameters

history	branching and inference history
dir	branching direction (downwards, or upwards)

Definition at line 477 of file history.c.

References NULL, SCIP_History::pscostcount, SCIP_BRANCHDIR_DOWNWARDS, and SCIP_BRANCHDIR_UPWARDS.

Referenced by SCIPgetAvgPseudocostCount(), SCIPgetAvgPseudocostCountCurrentRun(), SCIPgetPseudocostCount(), SCIPprintBranchingStatistics(), SCIPvarGetPseudocost(), SCIPvarGetPseudocostCount(), SCIPvarGetPseudocostCountCurrentRun(), and SCIPvarGetPseudocostCurrentRun().

◆ SCIPhistoryIsPseudocostEmpty()

SCIP_Bool SCIPhistoryIsPseudocostEmpty	(	SCIP_HISTORY *	history,
		SCIP_BRANCHDIR	dir
	)

returns whether the pseudo cost entry is empty in the given branching direction (whether no value was added yet)

Parameters

history	branching and inference history
dir	branching direction (downwards, or upwards)

Definition at line 490 of file history.c.

References NULL, SCIP_History::pscostcount, SCIP_BRANCHDIR_DOWNWARDS, and SCIP_BRANCHDIR_UPWARDS.

◆ SCIPhistoryIncVSIDS()

void SCIPhistoryIncVSIDS	(	SCIP_HISTORY *	history,
		SCIP_BRANCHDIR	dir,
		SCIP_Real	weight
	)

increases the conflict score of the history entry by the given weight

Parameters

history	branching and inference history
dir	branching direction
weight	weight of this update in conflict score

Definition at line 503 of file history.c.

References NULL, SCIP_BRANCHDIR_DOWNWARDS, SCIP_BRANCHDIR_UPWARDS, and SCIP_History::vsids.

Referenced by incVSIDS(), and SCIPvarIncVSIDS().

◆ SCIPhistoryScaleVSIDS()

void SCIPhistoryScaleVSIDS	(	SCIP_HISTORY *	history,
		SCIP_Real	scalar
	)

scales the conflict score values with the given scalar

Parameters

history	branching and inference history
scalar	scalar to multiply the conflict scores with

Definition at line 517 of file history.c.

References NULL, and SCIP_History::vsids.

Referenced by SCIPconflictInit(), SCIPvaluehistoryScaleVSIDS(), and SCIPvarScaleVSIDS().

◆ SCIPhistoryIncNActiveConflicts()

void SCIPhistoryIncNActiveConflicts	(	SCIP_HISTORY *	history,
		SCIP_BRANCHDIR	dir,
		SCIP_Real	length
	)

increases the number of active conflicts by one and the overall length of the history entry by the given weight

Parameters

history	branching and inference history
dir	branching direction
length	length of the conflict

Definition at line 542 of file history.c.

References SCIP_History::conflengthsum, SCIP_History::nactiveconflicts, NULL, SCIP_BRANCHDIR_DOWNWARDS, and SCIP_BRANCHDIR_UPWARDS.

Referenced by SCIPvarIncNActiveConflicts(), and updateStatistics().

◆ SCIPhistoryGetNActiveConflicts()

SCIP_Longint SCIPhistoryGetNActiveConflicts	(	SCIP_HISTORY *	history,
		SCIP_BRANCHDIR	dir
	)

gets the number of active conflicts of the history entry

Parameters

history	branching and inference history
dir	branching direction

Definition at line 558 of file history.c.

References SCIP_History::nactiveconflicts, NULL, SCIP_BRANCHDIR_DOWNWARDS, and SCIP_BRANCHDIR_UPWARDS.

Referenced by SCIPvarGetNActiveConflicts(), and SCIPvarGetNActiveConflictsCurrentRun().

◆ SCIPhistoryIncNBranchings()

void SCIPhistoryIncNBranchings	(	SCIP_HISTORY *	history,
		SCIP_BRANCHDIR	dir,
		int	depth
	)

increases the number of branchings counter

Parameters

history	branching and inference history
dir	branching direction (downwards, or upwards)
depth	depth at which the bound change took place

Definition at line 584 of file history.c.

References SCIP_History::branchdepthsum, SCIP_History::nbranchings, NULL, SCIP_BRANCHDIR_DOWNWARDS, and SCIP_BRANCHDIR_UPWARDS.

Referenced by SCIPreoptMergeVarHistory(), and SCIPvarIncNBranchings().

◆ SCIPhistoryIncInferenceSum()

void SCIPhistoryIncInferenceSum	(	SCIP_HISTORY *	history,
		SCIP_BRANCHDIR	dir,
		SCIP_Real	weight
	)

increases the number of inferences counter

increases the number of inferences counter by a certain value

Parameters

history	branching and inference history
dir	branching direction (downwards, or upwards)
weight	weight of this update in inference score

Definition at line 600 of file history.c.

References SCIP_History::inferencesum, SCIP_History::nbranchings, NULL, SCIP_BRANCHDIR_DOWNWARDS, and SCIP_BRANCHDIR_UPWARDS.

Referenced by SCIPreoptMergeVarHistory(), and SCIPvarIncInferenceSum().

◆ SCIPhistoryIncCutoffSum()

void SCIPhistoryIncCutoffSum	(	SCIP_HISTORY *	history,
		SCIP_BRANCHDIR	dir,
		SCIP_Real	weight
	)

increases the number of cutoffs counter

Parameters

history	branching and inference history
dir	branching direction (downwards, or upwards)
weight	weight of this update in cutoff score

Definition at line 616 of file history.c.

References SCIP_History::cutoffsum, SCIP_History::nbranchings, NULL, SCIP_BRANCHDIR_DOWNWARDS, and SCIP_BRANCHDIR_UPWARDS.

Referenced by SCIPreoptMergeVarHistory(), and SCIPvarIncCutoffSum().

◆ SCIPhistoryGetNBranchings()

SCIP_Longint SCIPhistoryGetNBranchings	(	SCIP_HISTORY *	history,
		SCIP_BRANCHDIR	dir
	)

get number of branchings counter

Parameters

history	branching and inference history
dir	branching direction (downwards, or upwards)

Definition at line 632 of file history.c.

References SCIP_History::nbranchings, NULL, SCIP_BRANCHDIR_DOWNWARDS, and SCIP_BRANCHDIR_UPWARDS.

Referenced by SCIPprintBranchingStatistics(), SCIPvarGetAvgCutoffs(), SCIPvarGetAvgCutoffsCurrentRun(), SCIPvarGetAvgInferences(), SCIPvarGetAvgInferencesCurrentRun(), SCIPvarGetNBranchings(), and SCIPvarGetNBranchingsCurrentRun().

◆ SCIPhistoryGetAvgInferences()

SCIP_Real SCIPhistoryGetAvgInferences	(	SCIP_HISTORY *	history,
		SCIP_BRANCHDIR	dir
	)

returns the average number of inferences per branching

Parameters

history	branching and inference history
dir	branching direction (downwards, or upwards)

Definition at line 658 of file history.c.

References SCIP_History::inferencesum, SCIP_History::nbranchings, NULL, SCIP_BRANCHDIR_DOWNWARDS, SCIP_BRANCHDIR_UPWARDS, and SCIP_Real.

Referenced by SCIPgetAvgInferences(), SCIPgetAvgInferenceScore(), SCIPgetAvgInferenceScoreCurrentRun(), SCIPgetAvgInferencesCurrentRun(), SCIPgetVarAvgInferenceCutoffScore(), SCIPgetVarAvgInferenceCutoffScoreCurrentRun(), SCIPreoptMergeVarHistory(), SCIPvarGetAvgInferences(), and SCIPvarGetAvgInferencesCurrentRun().

◆ SCIPhistoryGetAvgCutoffs()

SCIP_Real SCIPhistoryGetAvgCutoffs	(	SCIP_HISTORY *	history,
		SCIP_BRANCHDIR	dir
	)

returns the average number of cutoffs per branching

Parameters

history	branching and inference history
dir	branching direction (downwards, or upwards)

Definition at line 684 of file history.c.

References SCIP_History::cutoffsum, SCIP_History::nbranchings, NULL, SCIP_BRANCHDIR_DOWNWARDS, SCIP_BRANCHDIR_UPWARDS, and SCIP_Real.

Referenced by SCIPgetAvgCutoffs(), SCIPgetAvgCutoffScore(), SCIPgetAvgCutoffScoreCurrentRun(), SCIPgetAvgCutoffsCurrentRun(), SCIPreoptMergeVarHistory(), SCIPvarGetAvgCutoffs(), and SCIPvarGetAvgCutoffsCurrentRun().

◆ SCIPhistoryGetAvgBranchdepth()

SCIP_Real SCIPhistoryGetAvgBranchdepth	(	SCIP_HISTORY *	history,
		SCIP_BRANCHDIR	dir
	)

returns the average depth of bound changes due to branching

Parameters

history	branching and inference history
dir	branching direction (downwards, or upwards)

Definition at line 697 of file history.c.

References SCIP_History::branchdepthsum, SCIP_History::nbranchings, NULL, SCIP_BRANCHDIR_DOWNWARDS, SCIP_BRANCHDIR_UPWARDS, and SCIP_Real.

Referenced by SCIPvarGetAvgBranchdepth(), and SCIPvarGetAvgBranchdepthCurrentRun().

◆ SCIPhistoryIsRatioValid()

SCIP_Bool SCIPhistoryIsRatioValid ( SCIP_HISTORY * history )

returns true if the given history contains a valid ratio

Parameters

history branching and inference history

Definition at line 710 of file history.c.

References NULL, and SCIP_History::ratiovalid.

Referenced by computeVarRatio().

◆ SCIPhistoryGetLastRatio()

SCIP_Real SCIPhistoryGetLastRatio ( SCIP_HISTORY * history )

returns the most recent ratio computed given the variable history

Parameters

history branching and inference history

Definition at line 720 of file history.c.

References NULL, SCIP_History::ratio, and SCIP_History::ratiovalid.

Referenced by computeVarRatio().

◆ SCIPhistoryGetLastBalance()

SCIP_Real SCIPhistoryGetLastBalance ( SCIP_HISTORY * history )

returns the most recent value of r/l used to compute this variable's ratio

Parameters

history branching and inference history

Definition at line 731 of file history.c.

References SCIP_History::balance, NULL, and SCIP_History::ratiovalid.

Referenced by computeVarRatio().

◆ SCIPhistorySetRatioHistory()

void SCIPhistorySetRatioHistory	(	SCIP_HISTORY *	history,
		SCIP_Bool	valid,
		SCIP_Real	ratio,
		SCIP_Real	balance
	)

sets the ratio history for a particular variable

Parameters

history	branching and inference history
valid	True iff the ratio computed is valid
ratio	Ratio of the characteristic polynomial with gains (1, rightgain/leftgain)
balance	The value of rightgain/leftgain

Definition at line 742 of file history.c.

References SCIP_History::balance, NULL, SCIP_History::ratio, and SCIP_History::ratiovalid.

Referenced by computeVarRatio().

SCIP

Detailed Description

Functions

Function Documentation

◆ SCIPhistoryCreate()

◆ SCIPhistoryFree()

◆ SCIPhistoryReset()

◆ SCIPhistoryUnite()

◆ SCIPhistoryUpdatePseudocost()

◆ SCIPbranchdirOpposite()

◆ SCIPhistoryGetPseudocost()

◆ SCIPhistoryGetPseudocostVariance()

◆ SCIPhistoryGetPseudocostCount()

◆ SCIPhistoryIsPseudocostEmpty()

◆ SCIPhistoryIncVSIDS()

◆ SCIPhistoryScaleVSIDS()

◆ SCIPhistoryIncNActiveConflicts()

◆ SCIPhistoryGetNActiveConflicts()

◆ SCIPhistoryIncNBranchings()

◆ SCIPhistoryIncInferenceSum()

◆ SCIPhistoryIncCutoffSum()

◆ SCIPhistoryGetNBranchings()

◆ SCIPhistoryGetAvgInferences()

◆ SCIPhistoryGetAvgCutoffs()

◆ SCIPhistoryGetAvgBranchdepth()

◆ SCIPhistoryIsRatioValid()

◆ SCIPhistoryGetLastRatio()

◆ SCIPhistoryGetLastBalance()

◆ SCIPhistorySetRatioHistory()