Detailed Description

a linear inequality that is prepared to become a SCIP_ROW

This data structure helps to work around some limitations of SCIP_ROW's, in particular, that it rounds coefficients or sides close to integral values without the appropriate care. On the other hand, a SCIP_ROWPREP is limited to inequalities.

Functions
SCIP_RETCODE	SCIPcreateRowprep (SCIP scip, SCIP_ROWPREP *rowprep, SCIP_SIDETYPE sidetype, SCIP_Bool local)

void	SCIPfreeRowprep (SCIP scip, SCIP_ROWPREP *rowprep)

SCIP_RETCODE	SCIPcopyRowprep (SCIP scip, SCIP_ROWPREP target, SCIP_ROWPREP source)

int	SCIProwprepGetNVars (SCIP_ROWPREP *rowprep)

SCIP_VAR **	SCIProwprepGetVars (SCIP_ROWPREP *rowprep)

SCIP_Real *	SCIProwprepGetCoefs (SCIP_ROWPREP *rowprep)

SCIP_Real	SCIProwprepGetSide (SCIP_ROWPREP *rowprep)

SCIP_SIDETYPE	SCIProwprepGetSidetype (SCIP_ROWPREP *rowprep)

SCIP_Bool	SCIProwprepIsLocal (SCIP_ROWPREP *rowprep)

char *	SCIProwprepGetName (SCIP_ROWPREP *rowprep)

int	SCIProwprepGetNModifiedVars (SCIP_ROWPREP *rowprep)

SCIP_VAR **	SCIProwprepGetModifiedVars (SCIP_ROWPREP *rowprep)

void	SCIProwprepReset (SCIP_ROWPREP *rowprep)

void	SCIProwprepSetCoef (SCIP_ROWPREP *rowprep, int idx, SCIP_Real newcoef)

void	SCIProwprepAddSide (SCIP_ROWPREP *rowprep, SCIP_Real side)

void	SCIProwprepAddConstant (SCIP_ROWPREP *rowprep, SCIP_Real constant)

void	SCIProwprepSetSidetype (SCIP_ROWPREP *rowprep, SCIP_SIDETYPE sidetype)

void	SCIProwprepSetLocal (SCIP_ROWPREP *rowprep, SCIP_Bool islocal)

void	SCIProwprepRecordModifications (SCIP_ROWPREP *rowprep)

void	SCIPprintRowprep (SCIP scip, SCIP_ROWPREP rowprep, FILE *file)

void	SCIPprintRowprepSol (SCIP scip, SCIP_ROWPREP rowprep, SCIP_SOL sol, FILE file)

SCIP_RETCODE	SCIPensureRowprepSize (SCIP scip, SCIP_ROWPREP rowprep, int size)

SCIP_RETCODE	SCIPaddRowprepTerm (SCIP scip, SCIP_ROWPREP rowprep, SCIP_VAR *var, SCIP_Real coef)

SCIP_RETCODE	SCIPaddRowprepTerms (SCIP scip, SCIP_ROWPREP rowprep, int nvars, SCIP_VAR *vars, SCIP_Real coefs)

SCIP_Real	SCIPgetRowprepViolation (SCIP scip, SCIP_ROWPREP rowprep, SCIP_SOL sol, SCIP_Bool reliable)

SCIP_Bool	SCIPisRowprepViolationReliable (SCIP scip, SCIP_ROWPREP rowprep, SCIP_SOL *sol)

void	SCIPmergeRowprepTerms (SCIP scip, SCIP_ROWPREP rowprep)

SCIP_RETCODE	SCIPcleanupRowprep (SCIP scip, SCIP_ROWPREP rowprep, SCIP_SOL sol, SCIP_Real minviol, SCIP_Real viol, SCIP_Bool *success)

SCIP_RETCODE	SCIPcleanupRowprep2 (SCIP scip, SCIP_ROWPREP rowprep, SCIP_SOL sol, SCIP_Real maxcoefbound, SCIP_Bool success)

SCIP_Real	SCIPscaleupRowprep (SCIP scip, SCIP_ROWPREP rowprep, SCIP_Real minscaleup, SCIP_Bool *success)

int	SCIPscaleRowprep (SCIP_ROWPREP *rowprep, SCIP_Real factor)

SCIP_RETCODE	SCIPgetRowprepRowConshdlr (SCIP scip, SCIP_ROW row, SCIP_ROWPREP rowprep, SCIP_CONSHDLR *conshdlr)

SCIP_RETCODE	SCIPgetRowprepRowCons (SCIP scip, SCIP_ROW row, SCIP_ROWPREP rowprep, SCIP_CONS *cons)

SCIP_RETCODE	SCIPgetRowprepRowSepa (SCIP scip, SCIP_ROW row, SCIP_ROWPREP rowprep, SCIP_SEPA *sepa)

Function Documentation

◆ SCIPcreateRowprep()

SCIP_RETCODE SCIPcreateRowprep	(	SCIP *	scip,
		SCIP_ROWPREP **	rowprep,
		SCIP_SIDETYPE	sidetype,
		SCIP_Bool	local
	)

creates a SCIP_ROWPREP datastructure

Initial row represents 0 ≤ 0.

Parameters

scip	SCIP data structure
rowprep	buffer to store pointer to rowprep
sidetype	whether cut will be or lower-equal or larger-equal type
local	whether cut will be valid only locally

Definition at line 563 of file misc_rowprep.c.

References BMSclearMemory, NULL, SCIP_CALL, SCIP_OKAY, and SCIPallocBlockMemory.

Referenced by addCut(), generateCutSolDisagg(), generateCutSolSOC(), SCIP_DECL_NLHDLRENFO(), SCIP_DECL_NLHDLRESTIMATE(), SCIP_DECL_NLHDLRINITSEPA(), SCIP_DECL_NLHDLRSOLLINEARIZE(), and separateDeterminant().

◆ SCIPfreeRowprep()

void SCIPfreeRowprep	(	SCIP *	scip,
		SCIP_ROWPREP **	rowprep
	)

frees a SCIP_ROWPREP datastructure

Parameters

scip	SCIP data structure
rowprep	pointer that stores pointer to rowprep

Definition at line 583 of file misc_rowprep.c.

References NULL, SCIPfreeBlockMemory, and SCIPfreeBlockMemoryArrayNull.

Referenced by addCut(), enforceExprNlhdlr(), SCIP_DECL_NLHDLRENFO(), SCIP_DECL_NLHDLRESTIMATE(), SCIP_DECL_NLHDLRINITSEPA(), SCIP_DECL_NLHDLRSOLLINEARIZE(), and separateDeterminant().

◆ SCIPcopyRowprep()

SCIP_RETCODE SCIPcopyRowprep	(	SCIP *	scip,
		SCIP_ROWPREP **	target,
		SCIP_ROWPREP *	source
	)

creates a copy of a SCIP_ROWPREP datastructure

Parameters

scip	SCIP data structure
target	buffer to store pointer of rowprep copy
source	rowprep to copy

Definition at line 599 of file misc_rowprep.c.

References SCIP_RowPrep::coefs, FALSE, NULL, SCIP_CALL, SCIP_OKAY, SCIPduplicateBlockMemory, SCIPduplicateBlockMemoryArray, SCIP_RowPrep::vars, and SCIP_RowPrep::varssize.

◆ SCIProwprepGetNVars()

int SCIProwprepGetNVars ( SCIP_ROWPREP * rowprep )

gives number of terms in rowprep

Parameters

rowprep rowprep

Definition at line 629 of file misc_rowprep.c.

References NULL, and SCIP_RowPrep::nvars.

Referenced by addCutPool(), reformRowprep(), SCIP_DECL_NLHDLRENFO(), SCIP_DECL_NLHDLRINITSEPA(), SCIPprocessRowprepNonlinear(), and sparsifyIntercut().

◆ SCIProwprepGetVars()

SCIP_VAR** SCIProwprepGetVars ( SCIP_ROWPREP * rowprep )

gives variables of rowprep (feel free to modify)

Parameters

rowprep rowprep

Definition at line 639 of file misc_rowprep.c.

References NULL, and SCIP_RowPrep::vars.

Referenced by reformRowprep(), SCIP_DECL_NLHDLRENFO(), SCIPprocessRowprepNonlinear(), and sparsifyIntercut().

◆ SCIProwprepGetCoefs()

SCIP_Real* SCIProwprepGetCoefs ( SCIP_ROWPREP * rowprep )

gives coefficients of rowprep (feel free to modify)

Parameters

rowprep rowprep

Definition at line 649 of file misc_rowprep.c.

References SCIP_RowPrep::coefs, and NULL.

Referenced by estimateVertexPolyhedral(), reformRowprep(), SCIP_DECL_NLHDLRENFO(), SCIP_DECL_NLHDLRESTIMATE(), SCIP_DECL_NLHDLRSOLLINEARIZE(), SCIPprocessRowprepNonlinear(), and sparsifyIntercut().

◆ SCIProwprepGetSide()

SCIP_Real SCIProwprepGetSide ( SCIP_ROWPREP * rowprep )

gives side of rowprep

Parameters

rowprep rowprep

Definition at line 659 of file misc_rowprep.c.

References NULL, and SCIP_RowPrep::side.

Referenced by generateIntercut(), reformRowprep(), and SCIP_DECL_NLHDLRENFO().

◆ SCIProwprepGetSidetype()

SCIP_SIDETYPE SCIProwprepGetSidetype ( SCIP_ROWPREP * rowprep )

gives kind of inequality of rowprep

Parameters

rowprep rowprep

Definition at line 669 of file misc_rowprep.c.

References NULL, and SCIP_RowPrep::sidetype.

Referenced by enforceExprNlhdlr(), and SCIP_DECL_NLHDLRINITSEPA().

◆ SCIProwprepIsLocal()

SCIP_Bool SCIProwprepIsLocal ( SCIP_ROWPREP * rowprep )

returns whether rowprep is locally valid only

Parameters

rowprep rowprep

Definition at line 679 of file misc_rowprep.c.

References SCIP_RowPrep::local, and NULL.

Referenced by addCutPool(), and SCIP_DECL_NLHDLRSOLLINEARIZE().

◆ SCIProwprepGetName()

char* SCIProwprepGetName ( SCIP_ROWPREP * rowprep )

returns name of rowprep (feel free to modify)

Parameters

rowprep rowprep

Definition at line 689 of file misc_rowprep.c.

References SCIP_RowPrep::name, and NULL.

Referenced by addCut(), estimateBivariateQuotient(), estimateUnivariateQuotient(), generateCutSolDisagg(), generateCutSolSOC(), SCIP_DECL_NLHDLRENFO(), SCIP_DECL_NLHDLRESTIMATE(), SCIP_DECL_NLHDLRINITSEPA(), SCIP_DECL_NLHDLRSOLLINEARIZE(), and SCIPprocessRowprepNonlinear().

◆ SCIProwprepGetNModifiedVars()

int SCIProwprepGetNModifiedVars ( SCIP_ROWPREP * rowprep )

returns number of variables which coefficients were modified in cleanup

Parameters

rowprep rowprep

Definition at line 699 of file misc_rowprep.c.

References SCIP_RowPrep::nmodifiedvars, and NULL.

Referenced by SCIPprocessRowprepNonlinear().

◆ SCIProwprepGetModifiedVars()

SCIP_VAR** SCIProwprepGetModifiedVars ( SCIP_ROWPREP * rowprep )

returns variables which coefficients were modified in cleanup

Parameters

rowprep rowprep

Definition at line 709 of file misc_rowprep.c.

References SCIP_RowPrep::modifiedvars, and NULL.

Referenced by SCIPprocessRowprepNonlinear().

◆ SCIProwprepReset()

void SCIProwprepReset ( SCIP_ROWPREP * rowprep )

resets rowprep to have 0 terms and side 0.0

Parameters

rowprep rowprep

Definition at line 719 of file misc_rowprep.c.

References FALSE, SCIP_RowPrep::modifiedside, SCIP_RowPrep::nmodifiedvars, NULL, SCIP_RowPrep::nvars, SCIP_RowPrep::recordmodifications, and SCIP_RowPrep::side.

Referenced by SCIP_DECL_NLHDLRINITSEPA().

◆ SCIProwprepSetCoef()

void SCIProwprepSetCoef	(	SCIP_ROWPREP *	rowprep,
		int	idx,
		SCIP_Real	newcoef
	)

sets coefficient idx of rowprep

Parameters

rowprep	rowprep
idx	index of coef to set
newcoef	new coefficient

Definition at line 734 of file misc_rowprep.c.

References SCIP_RowPrep::coefs, and NULL.

Referenced by sparsifyIntercut().

◆ SCIProwprepAddSide()

void SCIProwprepAddSide	(	SCIP_ROWPREP *	rowprep,
		SCIP_Real	side
	)

adds constant value to side of rowprep

Parameters

rowprep	rowprep
side	constant value to be added to side

Definition at line 746 of file misc_rowprep.c.

References NULL, and SCIP_RowPrep::side.

Referenced by createRowprep(), generateCutSolDisagg(), generateCutSolSOC(), generateIntercut(), reformRowprep(), SCIProwprepAddConstant(), separateDeterminant(), and sparsifyIntercut().

◆ SCIProwprepAddConstant()

void SCIProwprepAddConstant	(	SCIP_ROWPREP *	rowprep,
		SCIP_Real	constant
	)

adds constant term to rowprep

Substracts constant from side.

Parameters

rowprep	rowprep
constant	constant value to be added

Definition at line 760 of file misc_rowprep.c.

References SCIProwprepAddSide().

Referenced by addColToCut(), addCut(), addRowToCut(), estimateConvexSecant(), estimateGradientInner(), estimateSpecialPower(), estimateVertexPolyhedral(), overEstimatePower(), rowprepCleanupImproveCoefrange(), rowprepCleanupIntegralCoefs(), SCIP_DECL_NLHDLRENFO(), SCIP_DECL_NLHDLRESTIMATE(), SCIP_DECL_NLHDLRINITSEPA(), SCIP_DECL_NLHDLRSOLLINEARIZE(), and underEstimatePower().

◆ SCIProwprepSetSidetype()

void SCIProwprepSetSidetype	(	SCIP_ROWPREP *	rowprep,
		SCIP_SIDETYPE	sidetype
	)

sets side type of rowprep

Parameters

rowprep	rowprep
sidetype	new side type

Definition at line 769 of file misc_rowprep.c.

References NULL, and SCIP_RowPrep::sidetype.

Referenced by generateIntercut(), and SCIP_DECL_NLHDLRINITSEPA().

◆ SCIProwprepSetLocal()

void SCIProwprepSetLocal	(	SCIP_ROWPREP *	rowprep,
		SCIP_Bool	islocal
	)

sets whether rowprep is local

Parameters

rowprep	rowprep
islocal	whether rowprep is local

Definition at line 780 of file misc_rowprep.c.

References SCIP_RowPrep::local, and NULL.

Referenced by estimateConvexSecant(), estimateGradientInner(), estimateUnivariateQuotient(), estimateVertexPolyhedral(), and SCIP_DECL_NLHDLRESTIMATE().

◆ SCIProwprepRecordModifications()

void SCIProwprepRecordModifications ( SCIP_ROWPREP * rowprep )

enables recording for where modifications were done in cleanup

Parameters

rowprep rowprep

Definition at line 791 of file misc_rowprep.c.

References NULL, SCIP_RowPrep::recordmodifications, and TRUE.

Referenced by SCIPprocessRowprepNonlinear().

◆ SCIPprintRowprep()

void SCIPprintRowprep	(	SCIP *	scip,
		SCIP_ROWPREP *	rowprep,
		FILE *	file
	)

prints a rowprep

Parameters

scip	SCIP data structure
rowprep	rowprep to be printed
file	file to print to, or NULL for stdout

Definition at line 801 of file misc_rowprep.c.

References SCIP_RowPrep::coefs, SCIP_RowPrep::local, SCIP_RowPrep::name, NULL, SCIP_RowPrep::nvars, SCIP_SIDETYPE_LEFT, SCIPinfoMessage(), SCIPvarGetName(), SCIP_RowPrep::side, SCIP_RowPrep::sidetype, and SCIP_RowPrep::vars.

Referenced by addCut(), estimateVertexPolyhedral(), SCIP_DECL_NLHDLRENFO(), SCIPcleanupRowprep(), SCIPcleanupRowprep2(), SCIPprocessRowprepNonlinear(), and SCIPscaleupRowprep().

◆ SCIPprintRowprepSol()

void SCIPprintRowprepSol	(	SCIP *	scip,
		SCIP_ROWPREP *	rowprep,
		SCIP_SOL *	sol,
		FILE *	file
	)

prints a rowprep and values in solution

Parameters

scip	SCIP data structure
rowprep	rowprep to be printed
sol	solution for activity
file	file to print to, or NULL for stdout

Definition at line 826 of file misc_rowprep.c.

References SCIP_RowPrep::coefs, SCIP_RowPrep::local, SCIP_RowPrep::name, NULL, SCIP_RowPrep::nvars, REALABS, SCIP_Real, SCIP_SIDETYPE_LEFT, SCIP_SIDETYPE_RIGHT, SCIPgetSolVal(), SCIPinfoMessage(), SCIPvarGetName(), SCIP_RowPrep::side, SCIP_RowPrep::sidetype, and SCIP_RowPrep::vars.

Referenced by SCIP_DECL_NLHDLRESTIMATE(), and SCIP_DECL_NLHDLRSOLLINEARIZE().

◆ SCIPensureRowprepSize()

SCIP_RETCODE SCIPensureRowprepSize	(	SCIP *	scip,
		SCIP_ROWPREP *	rowprep,
		int	size
	)

ensures that rowprep has space for at least given number of additional terms

Useful when knowing in advance how many terms will be added.

Parameters

scip	SCIP data structure
rowprep	rowprep
size	number of additional terms for which to alloc space in rowprep

Definition at line 887 of file misc_rowprep.c.

References SCIP_RowPrep::coefs, NULL, SCIP_RowPrep::nvars, SCIP_CALL, SCIP_OKAY, SCIPcalcMemGrowSize(), SCIPreallocBlockMemoryArray, SCIP_RowPrep::vars, and SCIP_RowPrep::varssize.

Referenced by createRowprep(), estimateVertexPolyhedral(), generateCutSolDisagg(), generateCutSolSOC(), SCIP_DECL_NLHDLRESTIMATE(), SCIP_DECL_NLHDLRINITSEPA(), SCIP_DECL_NLHDLRSOLLINEARIZE(), SCIPaddRowprepTerm(), and SCIPaddRowprepTerms().

◆ SCIPaddRowprepTerm()

SCIP_RETCODE SCIPaddRowprepTerm	(	SCIP *	scip,
		SCIP_ROWPREP *	rowprep,
		SCIP_VAR *	var,
		SCIP_Real	coef
	)

adds a term coef*var to a rowprep

Parameters

scip	SCIP data structure
rowprep	rowprep
var	variable to add
coef	coefficient to add

Definition at line 913 of file misc_rowprep.c.

References SCIP_RowPrep::coefs, NULL, SCIP_RowPrep::nvars, SCIP_CALL, SCIP_OKAY, SCIPensureRowprepSize(), SCIP_RowPrep::vars, and SCIP_RowPrep::varssize.

Referenced by addColToCut(), addRowToCut(), enforceExprNlhdlr(), estimateConvexSecant(), estimateGradientInner(), estimateSpecialPower(), estimateVertexPolyhedral(), generateCutSolDisagg(), generateCutSolSOC(), overEstimatePower(), SCIP_DECL_NLHDLRENFO(), SCIP_DECL_NLHDLRESTIMATE(), SCIP_DECL_NLHDLRINITSEPA(), SCIP_DECL_NLHDLRSOLLINEARIZE(), and underEstimatePower().

◆ SCIPaddRowprepTerms()

SCIP_RETCODE SCIPaddRowprepTerms	(	SCIP *	scip,
		SCIP_ROWPREP *	rowprep,
		int	nvars,
		SCIP_VAR **	vars,
		SCIP_Real *	coefs
	)

adds several terms coef*var to a rowprep

Parameters

scip	SCIP data structure
rowprep	rowprep
nvars	number of terms to add
vars	variables to add
coefs	coefficients to add

Definition at line 938 of file misc_rowprep.c.

References BMScopyMemoryArray, SCIP_RowPrep::coefs, NULL, SCIP_RowPrep::nvars, SCIP_CALL, SCIP_OKAY, SCIPensureRowprepSize(), SCIP_RowPrep::vars, and SCIP_RowPrep::varssize.

Referenced by addCut(), and createRowprep().

◆ SCIPgetRowprepViolation()

SCIP_Real SCIPgetRowprepViolation	(	SCIP *	scip,
		SCIP_ROWPREP *	rowprep,
		SCIP_SOL *	sol,
		SCIP_Bool *	reliable
	)

computes violation of rowprep in a given solution

Can return whether the violation value is reliable from a floating-point accuracy point of view. The value will not be deemed reliable when its calculation involved the subtraction of large numbers. To be precise, the violation of an inequality \( \sum_i a_ix_i \leq b \) in a solution \(x^*\) is deemed reliable if \( |\sum_i a_ix^*_i - b| \geq 2^{-50} \max (|b|, \max_i |a_ix^*_i|) \).

Parameters

scip	SCIP data structure
rowprep	rowprep
sol	solution or NULL for LP solution
reliable	buffer to store whether computed violation is reliable (numerically), or NULL if not of interest

Definition at line 972 of file misc_rowprep.c.

References SCIP_RowPrep::coefs, MAX, NULL, SCIP_RowPrep::nvars, REALABS, SCIP_Real, SCIP_SIDETYPE_RIGHT, SCIP_VARSTATUS_LOOSE, SCIPgetSolVal(), SCIPinfinity(), SCIPisInfinity(), SCIPvarGetStatus(), SCIP_RowPrep::side, SCIP_RowPrep::sidetype, TRUE, and SCIP_RowPrep::vars.

Referenced by addCut(), SCIPcleanupRowprep(), SCIPisRowprepViolationReliable(), and SCIPprocessRowprepNonlinear().

◆ SCIPisRowprepViolationReliable()

SCIP_Bool SCIPisRowprepViolationReliable	(	SCIP *	scip,
		SCIP_ROWPREP *	rowprep,
		SCIP_SOL *	sol
	)

computes violation of rowprep in a given solution and reports whether that value seem numerically reliable

See also: SCIPgetRowprepViolation()

Parameters

scip	SCIP data structure
rowprep	rowprep
sol	solution or NULL for LP solution

Definition at line 1064 of file misc_rowprep.c.

References NULL, SCIP_Bool, and SCIPgetRowprepViolation().

◆ SCIPmergeRowprepTerms()

void SCIPmergeRowprepTerms	(	SCIP *	scip,
		SCIP_ROWPREP *	rowprep
	)

Merge terms that use same variable and eliminate zero coefficients.

Removes a variable if its bounds have a relative difference of below epsilon. Local bounds are checked for local rows, otherwise global bounds are used. If the bounds are not absolute equal, the bound that relaxes the row is used.

Terms are sorted by variable (see SCIPvarComp()) after return.

Parameters

scip	SCIP data structure
rowprep	rowprep to be cleaned up

Definition at line 1088 of file misc_rowprep.c.

References SCIP_RowPrep::coefs, SCIP_RowPrep::local, NULL, SCIP_RowPrep::nvars, SCIP_SIDETYPE_RIGHT, SCIPisRelEQ(), SCIPsortPtrReal(), SCIPvarGetLbGlobal(), SCIPvarGetLbLocal(), SCIPvarGetUbGlobal(), SCIPvarGetUbLocal(), SCIP_RowPrep::side, SCIP_RowPrep::sidetype, and SCIP_RowPrep::vars.

Referenced by SCIP_DECL_NLHDLRENFO(), and separateDeterminant().

◆ SCIPcleanupRowprep()

SCIP_RETCODE SCIPcleanupRowprep	(	SCIP *	scip,
		SCIP_ROWPREP *	rowprep,
		SCIP_SOL *	sol,
		SCIP_Real	minviol,
		SCIP_Real *	viol,
		SCIP_Bool *	success
	)

Cleans up and attempts to improve rowprep

Drops small or large coefficients if their ratio is beyond separating/maxcoefratiofacrowprep / numerics/feastol, if this can be done by relaxing the row. Scales coefficients up to reach minimal violation, if possible. Scaling is omitted if violation is very small (ROWPREP_SCALEUP_VIOLNONZERO) or maximal coefficient would become huge (ROWPREP_SCALEUP_MAXMAXCOEF). Scales coefficients and side down if they are large and if the minimal violation is still reached. Rounds coefficients close to integral values to integrals, if this can be done by relaxing the row. Rounds side within epsilon of 0 to 0.0 or +/-1.1*epsilon, whichever relaxes the row least.

After return, the terms in the rowprep will be sorted by absolute value of coefficient, in decreasing order. Thus, the coefratio can be obtained via REALABS(rowprep->coefs[0]) / REALABS(rowprep->coefs[rowprep->nvars-1]) (if nvars>0).

success is set to TRUE if and only if the rowprep satisfies the following:

the coefratio is below separating/maxcoefratiofacrowprep / numerics/feastol
the violation is at least minviol
the violation is reliable or minviol = 0
the absolute value of coefficients are below SCIPinfinity()
the absolute value of the side is below SCIPinfinity()

Cleans up and attempts to improve rowprep

Drops small or large coefficients if coefrange is too large, if this can be done by relaxing the row. Scales coefficients up to reach minimal violation, if possible. Scaling is omitted if violation is very small (ROWPREP_SCALEUP_VIOLNONZERO) or maximal coefficient would become huge (ROWPREP_SCALEUP_MAXMAXCOEF). Scales coefficients and side down if they are large and if the minimal violation is still reached. Rounds coefficients close to integral values to integrals, if this can be done by relaxing the row. Rounds side within epsilon of 0 to 0.0 or +/-1.1*epsilon, whichever relaxes the row least.

After return, the terms in the rowprep will be sorted by absolute value of coefficient, in decreasing order. Thus, the coefrange can be obtained via REALABS(rowprep->coefs[0]) / REALABS(rowprep->coefs[rowprep->nvars-1]) (if nvars>0).

success is set to TRUE if and only if the rowprep satisfies the following:

the coefrange is below maxcoefrange
the violation is at least minviol
the violation is reliable or minviol = 0
the absolute value of coefficients are below SCIPinfinity()
the absolute value of the side is below SCIPinfinity()

Parameters

scip	SCIP data structure
rowprep	rowprep to be cleaned
sol	solution that we try to cut off, or NULL for LP solution
minviol	minimal absolute violation the row should achieve (w.r.t. sol)
viol	buffer to store absolute violation of cleaned up cut in sol, or NULL if not of interest
success	buffer to store whether cut cleanup was successful, or NULL if not of interest

Definition at line 1201 of file misc_rowprep.c.

References SCIP_RowPrep::coefs, FALSE, MAX, SCIP_RowPrep::modifiedside, SCIP_RowPrep::nmodifiedvars, NULL, SCIP_RowPrep::nvars, REALABS, SCIP_RowPrep::recordmodifications, rowprepCleanupImproveCoefrange(), rowprepCleanupIntegralCoefs(), rowprepCleanupScaledown(), rowprepCleanupScaleup(), rowprepCleanupSide(), rowprepCleanupSortTerms(), SCIP_Bool, SCIP_CALL, SCIP_INVALID, SCIP_OKAY, SCIP_Real, SCIPdebugMsg, SCIPgetRowprepViolation(), SCIPgetSepaMinEfficacy(), SCIPinfoMessage(), SCIPisInfinity(), SCIPprintRowprep(), SCIPsetGetSepaMaxCoefRatioRowprep(), Scip::set, SCIP_RowPrep::side, and TRUE.

Referenced by addCut(), SCIP_DECL_NLHDLRENFO(), SCIPprocessRowprepNonlinear(), and separateDeterminant().

◆ SCIPcleanupRowprep2()

SCIP_RETCODE SCIPcleanupRowprep2	(	SCIP *	scip,
		SCIP_ROWPREP *	rowprep,
		SCIP_SOL *	sol,
		SCIP_Real	maxcoefbound,
		SCIP_Bool *	success
	)

Cleans up and attempts to improve rowprep without regard for violation

Drops small or large coefficients if their ratio is beyond separating/maxcoefratiofacrowprep / numerics/feastol, if this can be done by relaxing the row. Scales coefficients and side to have maximal coefficient in [1/maxcoefbound,maxcoefbound]. Rounds coefficients close to integral values to integrals, if this can be done by relaxing the row. Rounds side within epsilon of 0 to 0.0 or +/-1.1*epsilon, whichever relaxes the row least.

After return, the terms in the rowprep will be sorted by absolute value of coefficient, in decreasing order. Thus, the coefratio can be obtained via REALABS(rowprep->coefs[0]) / REALABS(rowprep->coefs[rowprep->nvars-1]) (if nvars>0).

success is set to TRUE if and only if the rowprep satisfies the following:

the coefratio is below separating/maxcoefratiofacrowprep / numerics/feastol
the absolute value of coefficients are below SCIPinfinity()
the absolute value of the side is below SCIPinfinity()

In difference to SCIPcleanupRowprep(), this function does not scale up the row to increase the absolute violation.

Parameters

scip	SCIP data structure
rowprep	rowprep to be cleaned
sol	solution that we try to cut off, or NULL for LP solution
maxcoefbound	bound on absolute value of largest coefficient
success	buffer to store whether cut cleanup was successful, or NULL if not of interest

Definition at line 1376 of file misc_rowprep.c.

References SCIP_RowPrep::coefs, FALSE, SCIP_RowPrep::modifiedside, SCIP_RowPrep::nmodifiedvars, NULL, SCIP_RowPrep::nvars, REALABS, SCIP_RowPrep::recordmodifications, rowprepCleanupImproveCoefrange(), rowprepCleanupIntegralCoefs(), rowprepCleanupSide(), rowprepCleanupSortTerms(), SCIP_CALL, SCIP_OKAY, SCIP_Real, SCIPdebugMsg, SCIPinfoMessage(), SCIPisInfinity(), SCIPprintRowprep(), SCIPscaleRowprep(), SCIPsetGetSepaMaxCoefRatioRowprep(), Scip::set, SCIP_RowPrep::side, and TRUE.

Referenced by addCut(), addCutPool(), SCIP_DECL_NLHDLRINITSEPA(), SCIP_DECL_NLHDLRSOLLINEARIZE(), and SCIPprocessRowprepNonlinear().

◆ SCIPscaleupRowprep()

SCIP_Real SCIPscaleupRowprep	(	SCIP *	scip,
		SCIP_ROWPREP *	rowprep,
		SCIP_Real	minscaleup,
		SCIP_Bool *	success
	)

Scales up a rowprep to increase coefficients/sides that are within epsilon to an integer value, if possible.

Computes the minimal fractionality of all fractional coefficients and the side of the rowprep. If this fractionality is below epsilon, the rowprep is scaled up such that the fractionality exceeds epsilon, if this will not put any coefficient or side above SCIPhugeValue().

This function does not relax the rowprep.

success is set to TRUE if the resulting rowprep can be turned into a SCIP_ROW, that is, all coefs and the side is below SCIPinfinity() and fractionalities are above epsilon. If success is set to FALSE, then the rowprep will not have been modified.

Returns: The applied scaling factor, if success is set to TRUE.

Parameters

scip	SCIP data structure
rowprep	rowprep to be cleaned
minscaleup	minimal factor by which to scale up row, or <= 1.0 if to be ignored
success	buffer to store whether rowprep could be turned into SCIP_ROW without loss, or NULL if not of interest

Definition at line 1504 of file misc_rowprep.c.

References SCIP_RowPrep::coefs, FALSE, M_SQRT2, MAX, MIN, NULL, SCIP_RowPrep::nvars, REALABS, SCIP_Bool, SCIP_Real, SCIPdebugMsg, SCIPepsilon(), SCIPinfoMessage(), SCIPisHugeValue(), SCIPisInfinity(), SCIPprintRowprep(), SCIPscaleRowprep(), SCIP_RowPrep::side, and TRUE.

Referenced by SCIP_DECL_NLHDLRINITSEPA().

◆ SCIPscaleRowprep()

int SCIPscaleRowprep	(	SCIP_ROWPREP *	rowprep,
		SCIP_Real	factor
	)

scales a rowprep by given factor (after some rounding)

Returns: Exponent of actually applied scaling factor, if written as \(2^x\).

Parameters

rowprep	rowprep to be scaled
factor	suggested scale factor

Definition at line 1626 of file misc_rowprep.c.

References SCIP_RowPrep::coefs, NULL, SCIP_RowPrep::nvars, and SCIP_RowPrep::side.

Referenced by rowprepCleanupIntegralCoefs(), rowprepCleanupScaledown(), rowprepCleanupScaleup(), SCIPcleanupRowprep2(), and SCIPscaleupRowprep().

◆ SCIPgetRowprepRowConshdlr()

SCIP_RETCODE SCIPgetRowprepRowConshdlr	(	SCIP *	scip,
		SCIP_ROW **	row,
		SCIP_ROWPREP *	rowprep,
		SCIP_CONSHDLR *	conshdlr
	)

generates a SCIP_ROW from a rowprep, setting its origin to given constraint handler

Parameters

scip	SCIP data structure
row	buffer to store pointer to new row
rowprep	rowprep to be turned into a row
conshdlr	constraint handler

Definition at line 1655 of file misc_rowprep.c.

References SCIP_RowPrep::coefs, FALSE, SCIP_RowPrep::local, SCIP_RowPrep::name, NULL, SCIP_RowPrep::nvars, SCIP_CALL, SCIP_OKAY, SCIP_SIDETYPE_LEFT, SCIP_SIDETYPE_RIGHT, SCIPaddVarsToRow(), SCIPcreateEmptyRowConshdlr(), SCIPgetDepth(), SCIPinfinity(), SCIP_RowPrep::side, SCIP_RowPrep::sidetype, TRUE, and SCIP_RowPrep::vars.

◆ SCIPgetRowprepRowCons()

SCIP_RETCODE SCIPgetRowprepRowCons	(	SCIP *	scip,
		SCIP_ROW **	row,
		SCIP_ROWPREP *	rowprep,
		SCIP_CONS *	cons
	)

generates a SCIP_ROW from a rowprep, setting its origin to given constraint

Parameters

scip	SCIP data structure
row	buffer to store pointer to new row
rowprep	rowprep to be turned into a row
cons	constraint

Definition at line 1678 of file misc_rowprep.c.

References SCIP_RowPrep::coefs, FALSE, SCIP_RowPrep::local, SCIP_RowPrep::name, NULL, SCIP_RowPrep::nvars, SCIP_CALL, SCIP_OKAY, SCIP_SIDETYPE_LEFT, SCIP_SIDETYPE_RIGHT, SCIPaddVarsToRow(), SCIPcreateEmptyRowCons(), SCIPgetDepth(), SCIPinfinity(), SCIP_RowPrep::side, SCIP_RowPrep::sidetype, TRUE, and SCIP_RowPrep::vars.

Referenced by addCut(), addCutPool(), SCIP_DECL_NLHDLRENFO(), SCIP_DECL_NLHDLRINITSEPA(), SCIP_DECL_NLHDLRSOLLINEARIZE(), and SCIPprocessRowprepNonlinear().

◆ SCIPgetRowprepRowSepa()

SCIP_RETCODE SCIPgetRowprepRowSepa	(	SCIP *	scip,
		SCIP_ROW **	row,
		SCIP_ROWPREP *	rowprep,
		SCIP_SEPA *	sepa
	)

generates a SCIP_ROW from a rowprep, setting its origin to given separator

Parameters

scip	SCIP data structure
row	buffer to store pointer to new row
rowprep	rowprep to be turned into a row
sepa	separator

Definition at line 1701 of file misc_rowprep.c.

References SCIP_RowPrep::coefs, FALSE, SCIP_RowPrep::local, SCIP_RowPrep::name, NULL, SCIP_RowPrep::nvars, SCIP_CALL, SCIP_OKAY, SCIP_SIDETYPE_LEFT, SCIP_SIDETYPE_RIGHT, SCIPaddVarsToRow(), SCIPcreateEmptyRowSepa(), SCIPgetDepth(), SCIPinfinity(), SCIP_RowPrep::side, SCIP_RowPrep::sidetype, TRUE, and SCIP_RowPrep::vars.

Referenced by addCut(), and separateDeterminant().

SCIP

Detailed Description

Functions

Function Documentation

◆ SCIPcreateRowprep()

◆ SCIPfreeRowprep()

◆ SCIPcopyRowprep()

◆ SCIProwprepGetNVars()

◆ SCIProwprepGetVars()

◆ SCIProwprepGetCoefs()

◆ SCIProwprepGetSide()

◆ SCIProwprepGetSidetype()

◆ SCIProwprepIsLocal()

◆ SCIProwprepGetName()

◆ SCIProwprepGetNModifiedVars()

◆ SCIProwprepGetModifiedVars()

◆ SCIProwprepReset()

◆ SCIProwprepSetCoef()

◆ SCIProwprepAddSide()

◆ SCIProwprepAddConstant()

◆ SCIProwprepSetSidetype()

◆ SCIProwprepSetLocal()

◆ SCIProwprepRecordModifications()

◆ SCIPprintRowprep()

◆ SCIPprintRowprepSol()

◆ SCIPensureRowprepSize()

◆ SCIPaddRowprepTerm()

◆ SCIPaddRowprepTerms()

◆ SCIPgetRowprepViolation()

◆ SCIPisRowprepViolationReliable()

◆ SCIPmergeRowprepTerms()

◆ SCIPcleanupRowprep()

◆ SCIPcleanupRowprep2()

◆ SCIPscaleupRowprep()

◆ SCIPscaleRowprep()

◆ SCIPgetRowprepRowConshdlr()

◆ SCIPgetRowprepRowCons()

◆ SCIPgetRowprepRowSepa()