sepa_cmir.c File Reference

Detailed Description

complemented mixed integer rounding cuts separator (Marchand's version)

Author

Kati Wolter

Tobias Achterberg

Definition in file sepa_cmir.c.

#include <assert.h>
#include <string.h>
#include "scip/sepa_cmir.h"
#include "scip/pub_misc.h"

Go to the source code of this file.

Macros
#define	SEPA_NAME   "cmir"
#define	SEPA_DESC   "complemented mixed integer rounding cuts separator (Marchand's version)"
#define	SEPA_PRIORITY   -3000
#define	SEPA_FREQ   0
#define	SEPA_MAXBOUNDDIST   0.0
#define	SEPA_USESSUBSCIP   FALSE
#define	SEPA_DELAY   FALSE
#define	DEFAULT_MAXROUNDS   3
#define	DEFAULT_MAXROUNDSROOT   10
#define	DEFAULT_MAXTRIES   100
#define	DEFAULT_MAXTRIESROOT   -1
#define	DEFAULT_MAXFAILS   20
#define	DEFAULT_MAXFAILSROOT   100
#define	DEFAULT_MAXAGGRS   3
#define	DEFAULT_MAXAGGRSROOT   6
#define	DEFAULT_MAXSEPACUTS   100
#define	DEFAULT_MAXSEPACUTSROOT   500
#define	DEFAULT_MAXSLACK   0.0
#define	DEFAULT_MAXSLACKROOT   0.1
#define	DEFAULT_DENSITYSCORE   1e-04
#define	DEFAULT_SLACKSCORE   1e-03
#define	DEFAULT_MAXAGGDENSITY   0.20
#define	DEFAULT_MAXROWDENSITY   0.05
#define	DEFAULT_DENSITYOFFSET   100
#define	DEFAULT_MAXROWFAC   1e+4
#define	DEFAULT_MAXTESTDELTA   -1
#define	DEFAULT_MAXCONTS   10
#define	DEFAULT_MAXCONTSROOT   10
#define	DEFAULT_AGGRTOL   0.1
#define	DEFAULT_TRYNEGSCALING   TRUE
#define	DEFAULT_FIXINTEGRALRHS   TRUE
#define	DEFAULT_DYNAMICCUTS   TRUE
#define	BOUNDSWITCH   0.5
#define	USEVBDS   TRUE
#define	ALLOWLOCAL   TRUE
#define	MINFRAC   0.05
#define	MAXFRAC   0.999
#define	MAKECONTINTEGRAL   FALSE
#define	IMPLINTSARECONT
#define	MAXAGGRLEN(nvars)    (0.1*(nvars)+1000)

Functions
static SCIP_RETCODE	storeCutInArrays (SCIP *scip, int nvars, SCIP_VAR **vars, SCIP_Real *cutcoefs, SCIP_Real *varsolvals, SCIP_VAR **cutvars, SCIP_Real *cutvals, int *cutlen, SCIP_Real *cutact)
static SCIP_RETCODE	addCut (SCIP *scip, SCIP_SEPA *sepa, SCIP_SOL *sol, SCIP_Real *varsolvals, SCIP_Real *cutcoefs, SCIP_Real cutrhs, SCIP_Bool cutislocal, SCIP_Bool cutremovable, int cutrank, const char *cutclassname, SCIP_Bool *cutoff, int *ncuts)
static void	updateNActiveConts (SCIP *scip, SCIP_Real *varsolvals, SCIP_Real *bestcontlbs, SCIP_Real *bestcontubs, int nintvars, SCIP_VAR *var, int delta, int *nactiveconts)
static void	decreaseRowScore (SCIP *scip, SCIP_Real *rowlhsscores, SCIP_Real *rowrhsscores, int rowidx)
static SCIP_RETCODE	tryDelta (SCIP *scip, SCIP_SOL *sol, int nvars, SCIP_Real *rowweights, SCIP_Real maxweight, int *weightinds, int nweightinds, int rowlensum, SCIP_Real *cutcoefs, SCIP_Real *mksetcoefs, SCIP_Bool *mksetcoefsvalid, SCIP_Real *testeddeltas, int *ntesteddeltas, SCIP_Real delta, SCIP_Real boundswitch, SCIP_Bool usevbds, SCIP_Bool allowlocal, SCIP_Bool fixintegralrhs, int maxmksetcoefs, SCIP_Real maxweightrange, SCIP_Real minfrac, SCIP_Real maxfrac, SCIP_Real *bestdelta, SCIP_Real *bestefficacy)
SCIP_RETCODE	SCIPcutGenerationHeuristicCmir (SCIP *scip, SCIP_SEPA *sepa, SCIP_SOL *sol, SCIP_Real *varsolvals, int maxtestdelta, SCIP_Real *rowweights, SCIP_Real maxweight, int *weightinds, int nweightinds, int rowlensum, SCIP_Real boundswitch, SCIP_Bool usevbds, SCIP_Bool allowlocal, SCIP_Bool fixintegralrhs, int maxmksetcoefs, SCIP_Real maxweightrange, SCIP_Real minfrac, SCIP_Real maxfrac, SCIP_Bool trynegscaling, SCIP_Bool cutremovable, const char *cutclassname, SCIP_Bool *cutoff, int *ncuts, SCIP_Real *delta, SCIP_Bool *deltavalid)
static SCIP_Bool	varIsContinuous (SCIP_VAR *var)
static SCIP_Real	getBounddist (SCIP *scip, int nintvars, SCIP_Real *varsolvals, SCIP_Real *bestcontlbs, SCIP_Real *bestcontubs, SCIP_VAR *var)
static SCIP_RETCODE	aggregation (SCIP *scip, SCIP_SEPA *sepa, SCIP_SEPADATA *sepadata, SCIP_SOL *sol, SCIP_Real *varsolvals, SCIP_Real *bestcontlbs, SCIP_Real *bestcontubs, SCIP_Real *contvarscorebounds, SCIP_Real *rowlhsscores, SCIP_Real *rowrhsscores, int startrow, int maxaggrs, SCIP_Real maxslack, int maxconts, SCIP_Bool *wastried, SCIP_Bool *cutoff, int *ncuts)
static SCIP_RETCODE	separateCuts (SCIP *scip, SCIP_SEPA *sepa, SCIP_SOL *sol, SCIP_RESULT *result)
static	SCIP_DECL_SEPACOPY (sepaCopyCmir)
static	SCIP_DECL_SEPAFREE (sepaFreeCmir)
static	SCIP_DECL_SEPAEXECLP (sepaExeclpCmir)
static	SCIP_DECL_SEPAEXECSOL (sepaExecsolCmir)
SCIP_RETCODE	SCIPincludeSepaCmir (SCIP *scip)

Macro Definition Documentation

#define SEPA_NAME   "cmir"

Definition at line 31 of file sepa_cmir.c.

#define SEPA_DESC   "complemented mixed integer rounding cuts separator (Marchand's version)"

Definition at line 32 of file sepa_cmir.c.

#define SEPA_PRIORITY   -3000

Definition at line 33 of file sepa_cmir.c.

#define SEPA_FREQ   0

Definition at line 34 of file sepa_cmir.c.

#define SEPA_MAXBOUNDDIST   0.0

Definition at line 35 of file sepa_cmir.c.

#define SEPA_USESSUBSCIP   FALSE

does the separator use a secondary SCIP instance?

Definition at line 36 of file sepa_cmir.c.

#define SEPA_DELAY   FALSE

should separation method be delayed, if other separators found cuts?

Definition at line 37 of file sepa_cmir.c.

#define DEFAULT_MAXROUNDS   3

maximal number of cmir separation rounds per node (-1: unlimited)

Definition at line 39 of file sepa_cmir.c.

#define DEFAULT_MAXROUNDSROOT   10

maximal number of cmir separation rounds in the root node (-1: unlimited)

Definition at line 40 of file sepa_cmir.c.

#define DEFAULT_MAXTRIES   100

maximal number of rows to start aggregation with per separation round (-1: unlimited)

Definition at line 41 of file sepa_cmir.c.

#define DEFAULT_MAXTRIESROOT   -1

maximal number of rows to start aggregation with per round in the root node (-1: unlimited)

Definition at line 44 of file sepa_cmir.c.

#define DEFAULT_MAXFAILS   20

maximal number of consecutive unsuccessful aggregation tries (-1: unlimited)

Definition at line 47 of file sepa_cmir.c.

#define DEFAULT_MAXFAILSROOT   100

maximal number of consecutive unsuccessful aggregation tries in the root node (-1: unlimited)

Definition at line 48 of file sepa_cmir.c.

#define DEFAULT_MAXAGGRS   3

maximal number of aggregations for each row per separation round

Definition at line 51 of file sepa_cmir.c.

#define DEFAULT_MAXAGGRSROOT   6

maximal number of aggregations for each row per round in the root node

Definition at line 52 of file sepa_cmir.c.

#define DEFAULT_MAXSEPACUTS   100

maximal number of cmir cuts separated per separation round

Definition at line 53 of file sepa_cmir.c.

#define DEFAULT_MAXSEPACUTSROOT   500

maximal number of cmir cuts separated per separation round in root node

Definition at line 54 of file sepa_cmir.c.

#define DEFAULT_MAXSLACK   0.0

maximal slack of rows to be used in aggregation

Definition at line 55 of file sepa_cmir.c.

#define DEFAULT_MAXSLACKROOT   0.1

maximal slack of rows to be used in aggregation in the root node

Definition at line 56 of file sepa_cmir.c.

#define DEFAULT_DENSITYSCORE   1e-04

weight of row density in the aggregation scoring of the rows

Definition at line 57 of file sepa_cmir.c.

#define DEFAULT_SLACKSCORE   1e-03

weight of slack in the aggregation scoring of the rows

Definition at line 58 of file sepa_cmir.c.

#define DEFAULT_MAXAGGDENSITY   0.20

maximal density of aggregated row

Definition at line 59 of file sepa_cmir.c.

#define DEFAULT_MAXROWDENSITY   0.05

maximal density of row to be used in aggregation

Definition at line 60 of file sepa_cmir.c.

#define DEFAULT_DENSITYOFFSET   100

additional number of variables allowed in row on top of density

Definition at line 61 of file sepa_cmir.c.

#define DEFAULT_MAXROWFAC   1e+4

maximal row aggregation factor

Definition at line 62 of file sepa_cmir.c.

#define DEFAULT_MAXTESTDELTA   -1

maximal number of different deltas to try (-1: unlimited)

Definition at line 63 of file sepa_cmir.c.

#define DEFAULT_MAXCONTS   10

maximal number of active continuous variables in aggregated row

Definition at line 64 of file sepa_cmir.c.

#define DEFAULT_MAXCONTSROOT   10

maximal number of active continuous variables in aggregated row in the root

Definition at line 65 of file sepa_cmir.c.

#define DEFAULT_AGGRTOL   0.1

aggregation heuristic: tolerance for bound distances used to select real variable in current aggregated constraint to be eliminated

Definition at line 66 of file sepa_cmir.c.

#define DEFAULT_TRYNEGSCALING   TRUE

should negative values also be tested in scaling?

Definition at line 69 of file sepa_cmir.c.

#define DEFAULT_FIXINTEGRALRHS   TRUE

should an additional variable be complemented if f0 = 0?

Definition at line 70 of file sepa_cmir.c.

#define DEFAULT_DYNAMICCUTS   TRUE

should generated cuts be removed from the LP if they are no longer tight?

Definition at line 71 of file sepa_cmir.c.

#define BOUNDSWITCH   0.5

Definition at line 73 of file sepa_cmir.c.

Referenced by aggregation().

#define USEVBDS   TRUE

Definition at line 74 of file sepa_cmir.c.

Referenced by aggregation().

#define ALLOWLOCAL   TRUE

Definition at line 75 of file sepa_cmir.c.

Referenced by aggregation(), and separateCuts().

#define MINFRAC   0.05

Definition at line 76 of file sepa_cmir.c.

Referenced by aggregation().

#define MAXFRAC   0.999

Definition at line 77 of file sepa_cmir.c.

Referenced by aggregation().

#define MAKECONTINTEGRAL   FALSE

Definition at line 78 of file sepa_cmir.c.

Referenced by addCut().

#define IMPLINTSARECONT

Definition at line 79 of file sepa_cmir.c.

#define MAXAGGRLEN

(

nvars

)

(0.1*(nvars)+1000)

maximal length of base inequality

Definition at line 81 of file sepa_cmir.c.

Referenced by aggregation().

Function Documentation

static SCIP_RETCODE storeCutInArrays ( SCIP *  scip, int  nvars, SCIP_VAR **  vars, SCIP_Real *  cutcoefs, SCIP_Real *  varsolvals, SCIP_VAR **  cutvars, SCIP_Real *  cutvals, int *  cutlen, SCIP_Real *  cutact  )

static

stores nonzero elements of dense coefficient vector as sparse vector, and calculates activity and norm

Parameters

scip	SCIP data structure
nvars	number of problem variables
vars	problem variables
cutcoefs	dense coefficient vector
varsolvals	dense variable LP solution vector
cutvars	array to store variables of sparse cut vector
cutvals	array to store coefficients of sparse cut vector
cutlen	pointer to store number of nonzero entries in cut
cutact	pointer to store activity of cut

Definition at line 129 of file sepa_cmir.c.

References addCut(), NULL, SCIP_OKAY, SCIP_Real, and SCIPisZero().

Referenced by addCut().

static SCIP_RETCODE addCut ( SCIP *  scip, SCIP_SEPA *  sepa, SCIP_SOL *  sol, SCIP_Real *  varsolvals, SCIP_Real *  cutcoefs, SCIP_Real  cutrhs, SCIP_Bool  cutislocal, SCIP_Bool  cutremovable, int  cutrank, const char *  cutclassname, SCIP_Bool *  cutoff, int *  ncuts  )

static

adds given cut to LP if violated

Parameters

scip	SCIP data structure
sepa	separator
sol	the solution that should be separated, or NULL for LP solution
varsolvals	solution values of active variables
cutcoefs	coefficients of active variables in cut
cutrhs	right hand side of cut
cutislocal	is the cut only locally valid?
cutremovable	should the cut be removed from the LP due to aging or cleanup?
cutrank	rank of the cut
cutclassname	name of cut class to use for row names
cutoff	whether a cutoff has been detected
ncuts	pointer to count the number of added cuts

Definition at line 176 of file sepa_cmir.c.

References FALSE, MAKECONTINTEGRAL, NULL, SCIP_Bool, SCIP_CALL, SCIP_Longint, SCIP_MAXSTRLEN, SCIP_OKAY, SCIP_Real, SCIPaddCut(), SCIPaddPoolCut(), SCIPaddVarsToRow(), SCIPallocBufferArray, SCIPcreateEmptyRowSepa(), SCIPdebug, SCIPdebugMessage, SCIPepsilon(), SCIPfreeBufferArray, SCIPgetCutEfficacy(), SCIPgetNLPs(), SCIPgetRowMaxCoef(), SCIPgetRowMinCoef(), SCIPgetVarsData(), SCIPgetVectorEfficacyNorm(), SCIPinfinity(), SCIPisCutEfficacious(), SCIPisEfficacious(), SCIPisPositive(), SCIPmakeRowIntegral(), SCIPprintRow(), SCIPreleaseRow(), SCIProwChgRank(), SCIProwGetRank(), SCIPsnprintf(), SCIPsumepsilon(), storeCutInArrays(), TRUE, and updateNActiveConts().

Referenced by SCIPcutGenerationHeuristicCmir(), and storeCutInArrays().

static void updateNActiveConts ( SCIP *  scip, SCIP_Real *  varsolvals, SCIP_Real *  bestcontlbs, SCIP_Real *  bestcontubs, int  nintvars, SCIP_VAR *  var, int  delta, int *  nactiveconts  )

static

adds delta to active continuous variables counter

Parameters

scip	SCIP data structure
varsolvals	LP solution value of all variables in LP
bestcontlbs	best lower (variable or standard) bounds of continuous variables
bestcontubs	best upper (variable or standard) bounds of continuous variables
nintvars	number of integer variables
var	continuous variable
delta	delta value of counters
nactiveconts	pointer to count number of active continuous variables

Definition at line 285 of file sepa_cmir.c.

References decreaseRowScore(), NULL, SCIP_Real, SCIPisLT(), SCIPvarGetProbindex(), and SCIPvarIsIntegral().

Referenced by addCut(), and aggregation().

static void decreaseRowScore ( SCIP *  scip, SCIP_Real *  rowlhsscores, SCIP_Real *  rowrhsscores, int  rowidx  )

static

decreases the score of a row in order to not aggregate it again too soon

Parameters

scip	SCIP data structure
rowlhsscores	aggregation scores for left hand sides of row
rowrhsscores	aggregation scores for right hand sides of row
rowidx	index of row to decrease score for

Definition at line 319 of file sepa_cmir.c.

References NULL, and tryDelta().

Referenced by aggregation(), and updateNActiveConts().

static SCIP_RETCODE tryDelta ( SCIP *  scip, SCIP_SOL *  sol, int  nvars, SCIP_Real *  rowweights, SCIP_Real  maxweight, int *  weightinds, int  nweightinds, int  rowlensum, SCIP_Real *  cutcoefs, SCIP_Real *  mksetcoefs, SCIP_Bool *  mksetcoefsvalid, SCIP_Real *  testeddeltas, int *  ntesteddeltas, SCIP_Real  delta, SCIP_Real  boundswitch, SCIP_Bool  usevbds, SCIP_Bool  allowlocal, SCIP_Bool  fixintegralrhs, int  maxmksetcoefs, SCIP_Real  maxweightrange, SCIP_Real  minfrac, SCIP_Real  maxfrac, SCIP_Real *  bestdelta, SCIP_Real *  bestefficacy  )

static

calculates the c-MIR cut for the given rowweights and delta value, and updates testeddeltas, bestdelta, and bestefficacy

Parameters

scip	SCIP data structure
sol	the solution that should be separated, or NULL for LP solution
nvars	number of problem variables
rowweights	weight of rows in aggregated row
maxweight	largest magnitude of weights; set to -1 if sparsity information is unknown
weightinds	sparsity pattern of weights; size nrowinds; NULL if sparsity info is unknown
nweightinds	number of nonzeros in weights; -1 if rowinds is NULL
rowlensum	total number of non-zeros in used rows (row associated with nonzero weight coefficient); -1 if unknown
cutcoefs	array to store the cut coefficients
mksetcoefs	array to store mixed knapsack set coefficients: size nvars; or NULL
mksetcoefsvalid	pointer to store whether mixed knapsack set coefficients are valid; or NULL
testeddeltas	array with already tested deltas
ntesteddeltas	pointer to the number of elements in testeddeltas
delta	delta value to scale mixed knapsack equation with
boundswitch	fraction of domain up to which lower bound is used in transformation
usevbds	should variable bounds be used in bound transformation?
allowlocal	should local information allowed to be used, resulting in a local cut?
fixintegralrhs	should complementation tried to be adjusted such that rhs gets fractional?
maxmksetcoefs	maximal number of nonzeros allowed in aggregated base inequality
maxweightrange	maximal valid range max(|weights|)/min(|weights|) of row weights
minfrac	minimal fractionality of rhs to produce MIR cut for
maxfrac	maximal fractionality of rhs to produce MIR cut for
bestdelta	pointer to the currently best delta value
bestefficacy	pointer to the currently best efficacy

Definition at line 339 of file sepa_cmir.c.

References FALSE, NULL, SCIP_Bool, SCIP_CALL, SCIP_OKAY, SCIP_Real, SCIPcalcMIR(), SCIPcutGenerationHeuristicCmir(), SCIPdebugMessage, SCIPgetVectorEfficacyNorm(), SCIPisEQ(), SCIPisFeasGT(), and SCIPisFeasZero().

Referenced by decreaseRowScore(), and SCIPcutGenerationHeuristicCmir().

SCIP_RETCODE SCIPcutGenerationHeuristicCmir	(	SCIP *	scip,
		SCIP_SEPA *	sepa,
		SCIP_SOL *	sol,
		SCIP_Real *	varsolvals,
		int	maxtestdelta,
		SCIP_Real *	rowweights,
		SCIP_Real	maxweight,
		int *	weightinds,
		int	nweightinds,
		int	rowlensum,
		SCIP_Real	boundswitch,
		SCIP_Bool	usevbds,
		SCIP_Bool	allowlocal,
		SCIP_Bool	fixintegralrhs,
		int	maxmksetcoefs,
		SCIP_Real	maxweightrange,
		SCIP_Real	minfrac,
		SCIP_Real	maxfrac,
		SCIP_Bool	trynegscaling,
		SCIP_Bool	cutremovable,
		const char *	cutclassname,
		SCIP_Bool *	cutoff,
		int *	ncuts,
		SCIP_Real *	delta,
		SCIP_Bool *	deltavalid
	)

Performs the cut generation heuristic of the c-MIR separation algorithm, i.e., tries to generate a c-MIR cut which is valid for the mixed knapsack set corresponding to the current aggregated constraint. Cuts will only be added here if no pointer to store best scaling factor delta is given.

Parameters

scip	SCIP data structure
sepa	separator
sol	the solution that should be separated, or NULL for LP solution
varsolvals	LP solution value of all variables in LP
maxtestdelta	maximal number of different deltas to try (-1: unlimited)
rowweights	weight of rows in aggregated row
maxweight	largest magnitude of weights; set to -1.0 if sparsity information is unknown
weightinds	sparsity pattern of weights; size nrowinds; NULL if sparsity info is unknown
nweightinds	number of nonzeros in weights; -1 if rowinds is NULL
rowlensum	total number of non-zeros in used rows (row associated with nonzero weight coefficient); -1 if unknown
boundswitch	fraction of domain up to which lower bound is used in transformation
usevbds	should variable bounds be used in bound transformation?
allowlocal	should local information allowed to be used, resulting in a local cut?
fixintegralrhs	should complementation tried to be adjusted such that rhs gets fractional?
maxmksetcoefs	maximal number of nonzeros allowed in aggregated base inequality
maxweightrange	maximal valid range max(|weights|)/min(|weights|) of row weights
minfrac	minimal fractionality of rhs to produce MIR cut for
maxfrac	maximal fractionality of rhs to produce MIR cut for
trynegscaling	should negative values also be tested in scaling?
cutremovable	should the cut be removed from the LP due to aging or cleanup?
cutclassname	name of cut class to use for row names
cutoff	whether a cutoff has been detected
ncuts	pointer to count the number of generated cuts
delta	pointer to store best delta found; NULL, if cut should be added here
deltavalid	pointer to store whether best delta value is valid or NULL

Definition at line 429 of file sepa_cmir.c.

References addCut(), FALSE, MAX, NULL, REALABS, SCIP_Bool, SCIP_CALL, SCIP_OKAY, SCIP_Real, SCIP_VARTYPE_CONTINUOUS, SCIPallocBufferArray, SCIPcalcMIR(), SCIPfreeBufferArray, SCIPgetNContVars(), SCIPgetNVars(), SCIPgetVars(), SCIPisEfficacious(), SCIPisEQ(), SCIPisFeasZero(), SCIPvarGetLbLocal(), SCIPvarGetProbindex(), SCIPvarGetType(), SCIPvarGetUbLocal(), SCIPvarIsActive(), SCIPvarIsIntegral(), TRUE, tryDelta(), and varIsContinuous().

Referenced by aggregation(), createZerohalfCutFromZerohalfWeightvector(), and tryDelta().

static SCIP_Bool varIsContinuous ( SCIP_VAR *  var )

static

returns whether the variable should be tried to be aggregated out

Parameters

var	problem variable

Definition at line 637 of file sepa_cmir.c.

Referenced by aggregation(), getBounddist(), and SCIPcutGenerationHeuristicCmir().

static SCIP_Real getBounddist ( SCIP *  scip, int  nintvars, SCIP_Real *  varsolvals, SCIP_Real *  bestcontlbs, SCIP_Real *  bestcontubs, SCIP_VAR *  var  )

static

returns the minimal distance of the solution of a continuous variable to its bounds

Parameters

scip	SCIP data structure
nintvars	number of integer variables in the problem
varsolvals	LP solution value of all variables in LP
bestcontlbs	best lower (variable or standard) bounds of continuous variables
bestcontubs	best upper (variable or standard) bounds of continuous variables
var	continuous variable to get bound distance for

Definition at line 654 of file sepa_cmir.c.

References aggregation(), MIN, SCIP_Real, SCIP_VARTYPE_CONTINUOUS, SCIPisGE(), SCIPisLE(), SCIPvarGetLbGlobal(), SCIPvarGetProbindex(), SCIPvarGetType(), SCIPvarGetUbGlobal(), and varIsContinuous().

Referenced by aggregation().

static SCIP_RETCODE aggregation ( SCIP *  scip, SCIP_SEPA *  sepa, SCIP_SEPADATA *  sepadata, SCIP_SOL *  sol, SCIP_Real *  varsolvals, SCIP_Real *  bestcontlbs, SCIP_Real *  bestcontubs, SCIP_Real *  contvarscorebounds, SCIP_Real *  rowlhsscores, SCIP_Real *  rowrhsscores, int  startrow, int  maxaggrs, SCIP_Real  maxslack, int  maxconts, SCIP_Bool *  wastried, SCIP_Bool *  cutoff, int *  ncuts  )

static

aggregates different single mixed integer constraints by taking linear combinations of the rows of the LP

Parameters

scip	SCIP data structure
sepa	separator
sepadata	separator data
sol	the solution that should be separated, or NULL for LP solution
varsolvals	LP solution value of all variables in LP
bestcontlbs	best lower (variable or standard) bounds of continuous variables
bestcontubs	best upper (variable or standard) bounds of continuous variables
contvarscorebounds	bounds on the maximal rowlhsscores and rowrhsscores the variable is contained in
rowlhsscores	aggregation scores for left hand sides of row
rowrhsscores	aggregation scores for right hand sides of row
startrow	index of row to start aggregation
maxaggrs	maximal number of aggregations
maxslack	maximal slack of rows to be used in aggregation
maxconts	maximal number of active continuous variables in aggregated row
wastried	pointer to store whether the given startrow was actually tried
cutoff	whether a cutoff has been detected
ncuts	pointer to count the number of generated cuts

Definition at line 693 of file sepa_cmir.c.

References ALLOWLOCAL, BMSclearMemoryArray, BOUNDSWITCH, decreaseRowScore(), FALSE, getBounddist(), MAX, MAXAGGRLEN, MAXFRAC, MIN, MINFRAC, NULL, REALABS, SCIP_Bool, SCIP_CALL, SCIP_OKAY, SCIP_Real, SCIPallocBufferArray, SCIPcolGetLPPos(), SCIPcolGetNLPNonz(), SCIPcolGetRows(), SCIPcolGetVals(), SCIPcolGetVar(), SCIPcutGenerationHeuristicCmir(), SCIPdebugMessage, SCIPdebugPrintf, SCIPfreeBufferArray, SCIPgetLPColsData(), SCIPgetLPRowsData(), SCIPgetNImplVars(), SCIPgetRowSolActivity(), SCIPgetVarsData(), SCIPisEQ(), SCIPisFeasIntegral(), SCIPisGT(), SCIPisInfinity(), SCIPisPositive(), SCIPisZero(), SCIProwGetCols(), SCIProwGetLhs(), SCIProwGetLPPos(), SCIProwGetName(), SCIProwGetNLPNonz(), SCIProwGetNNonz(), SCIProwGetRhs(), SCIProwGetVals(), SCIProwIsModifiable(), SCIPsortedvecInsertDownRealInt(), SCIPsortedvecInsertInt(), SCIPvarGetName(), SCIPvarGetProbindex(), SCIPvarIsIntegral(), separateCuts(), TRUE, updateNActiveConts(), USEVBDS, and varIsContinuous().

Referenced by getBounddist(), and separateCuts().

static SCIP_RETCODE separateCuts ( SCIP *  scip, SCIP_SEPA *  sepa, SCIP_SOL *  sol, SCIP_RESULT *  result  )

static

searches and adds c-MIR cuts that separate the given primal solution

Parameters

scip	SCIP data structure
sepa	the c-MIR separator
sol	the solution that should be separated, or NULL for LP solution
result	pointer to store the result

Definition at line 1228 of file sepa_cmir.c.

References aggregation(), ALLOWLOCAL, FALSE, MAX, MIN, NULL, SCIP_Bool, SCIP_CALL, SCIP_CUTOFF, SCIP_DECL_SEPACOPY(), SCIP_DIDNOTFIND, SCIP_DIDNOTRUN, SCIP_OKAY, SCIP_Real, SCIP_REAL_MAX, SCIP_SEPARATED, SCIPallocBufferArray, SCIPdebugMessage, SCIPfreeBufferArray, SCIPgetDepth(), SCIPgetLPRowsData(), SCIPgetNContVars(), SCIPgetNImplVars(), SCIPgetNSepaRounds(), SCIPgetNVars(), SCIPgetObjNorm(), SCIPgetRowSolActivity(), SCIPgetSolVals(), SCIPgetVarClosestVlb(), SCIPgetVarClosestVub(), SCIPgetVars(), SCIPisInfinity(), SCIPisLE(), SCIPisPositive(), SCIPisStopped(), SCIProwGetDualsol(), SCIProwGetLhs(), SCIProwGetLPPos(), SCIProwGetName(), SCIProwGetNLPNonz(), SCIProwGetNorm(), SCIProwGetRhs(), SCIProwIsLocal(), SCIPsepaGetData(), SCIPsepaGetNCallsAtNode(), SCIPvarGetLbGlobal(), SCIPvarGetLbLocal(), SCIPvarGetUbGlobal(), and SCIPvarGetUbLocal().

Referenced by aggregation().

static SCIP_DECL_SEPACOPY ( sepaCopyCmir  )

static

copy method for separator plugins (called when SCIP copies plugins)

Definition at line 1539 of file sepa_cmir.c.

Referenced by separateCuts().

static SCIP_DECL_SEPAFREE ( sepaFreeCmir  )

static

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

Definition at line 1553 of file sepa_cmir.c.

static SCIP_DECL_SEPAEXECLP ( sepaExeclpCmir  )

static

LP solution separation method of separator

Definition at line 1571 of file sepa_cmir.c.

static SCIP_DECL_SEPAEXECSOL ( sepaExecsolCmir  )

static

arbitrary primal solution separation method of separator

Definition at line 1596 of file sepa_cmir.c.

SCIP_RETCODE SCIPincludeSepaCmir

(

SCIP *

scip

)

creates the cmir separator and includes it in SCIP

Parameters

scip	SCIP data structure

Definition at line 1612 of file sepa_cmir.c.

Referenced by SCIPincludeDefaultPlugins().