Detailed Description

functions and files provided by the exact LP solver interface of SCIP

For the numerically exact solving mode, SCIP also uses exact LP solvers. The communication is realized through an exact LP interface.

This page lists public interface functions that every exact LP interface provides. Find the concrete implementation for your exact LP solver under "src/lpiexact/".

See also: Available implementations of the numerically exact LP solver interface for a list of available exact LP solver interfaces

This file specifies a generic interface for numerically exact LP solvers used by SCIP to create, modify, and solve linear programs with rational input data of the form

min/max   obj * x
   lhs <=   A * x  <= rhs
   lb  <=       x  <= ub

and query information about the solution. It is mainly a numerically exact analogue of the standard floating-point LP Solver Interface, so we refer to this documentation for further details on the design of the interface.

Files
file	lpiexact.h
	interface methods for specific exact LP solvers
file	lpiexact_none.c
	dummy interface for the case no LP solver is needed
file	lpiexact_qsoex.c
	exact LP interface for QSopt_ex version >= 2.5.4 (r239)
file	lpiexact_spx.cpp
	exact LP interface for SoPlex

Miscellaneous Methods
const char *	SCIPlpiExactGetSolverName (void)
const char *	SCIPlpiExactGetSolverDesc (void)
const char *	SCIPlpiExactGetExternalCodeName (void)
void	SCIPlpiExactPrintInfo (SCIP_LPIEXACT *lpi)
const char *	SCIPlpiExactGetExternalCodeDesc (void)
void *	SCIPlpiExactGetSolverPointer (SCIP_LPIEXACT *lpi)

LPI Creation and Destruction Methods
void	SCIPlpiExactStart (void)
void	SCIPlpiExactEnd (void)
SCIP_RETCODE	SCIPlpiExactCreate (SCIP_LPIEXACT *lpi, SCIP_MESSAGEHDLR messagehdlr, const char *name, SCIP_OBJSEN objsen)
SCIP_RETCODE	SCIPlpiExactFree (SCIP_LPIEXACT **lpi)

Modification Methods
SCIP_RETCODE	SCIPlpiExactLoadColLP (SCIP_LPIEXACT lpi, SCIP_OBJSEN objsen, int ncols, SCIP_RATIONAL obj, SCIP_RATIONAL lb, SCIP_RATIONAL ub, char colnames, int nrows, SCIP_RATIONAL lhs, SCIP_RATIONAL rhs, char rownames, int nnonz, int beg, int ind, SCIP_RATIONAL *val)
SCIP_RETCODE	SCIPlpiExactAddCols (SCIP_LPIEXACT lpi, int ncols, SCIP_RATIONAL obj, SCIP_RATIONAL lb, SCIP_RATIONAL ub, char colnames, int nnonz, int beg, int ind, SCIP_RATIONAL *val)
SCIP_RETCODE	SCIPlpiExactDelCols (SCIP_LPIEXACT *lpi, int firstcol, int lastcol)
SCIP_RETCODE	SCIPlpiExactDelColset (SCIP_LPIEXACT lpi, int dstat)
SCIP_RETCODE	SCIPlpiExactAddRows (SCIP_LPIEXACT lpi, int nrows, SCIP_RATIONAL lhs, SCIP_RATIONAL rhs, char rownames, int nnonz, int beg, int ind, SCIP_RATIONAL *val)
SCIP_RETCODE	SCIPlpiExactDelRows (SCIP_LPIEXACT *lpi, int firstrow, int lastrow)
SCIP_RETCODE	SCIPlpiExactDelRowset (SCIP_LPIEXACT lpi, int dstat)
SCIP_RETCODE	SCIPlpiExactClear (SCIP_LPIEXACT *lpi)
SCIP_RETCODE	SCIPlpiExactChgBounds (SCIP_LPIEXACT lpi, int ncols, int ind, SCIP_RATIONAL lb, SCIP_RATIONAL ub)
SCIP_RETCODE	SCIPlpiExactChgSides (SCIP_LPIEXACT lpi, int nrows, int ind, SCIP_RATIONAL lhs, SCIP_RATIONAL rhs)
SCIP_RETCODE	SCIPlpiExactChgCoef (SCIP_LPIEXACT lpi, int row, int col, SCIP_RATIONAL newval)
SCIP_RETCODE	SCIPlpiExactChgObjsen (SCIP_LPIEXACT *lpi, SCIP_OBJSEN objsen)
SCIP_RETCODE	SCIPlpiExactChgObj (SCIP_LPIEXACT lpi, int ncols, int ind, SCIP_RATIONAL **obj)
SCIP_RETCODE	SCIPlpiExactScaleRow (SCIP_LPIEXACT lpi, int row, SCIP_RATIONAL scaleval)
SCIP_RETCODE	SCIPlpiExactScaleCol (SCIP_LPIEXACT lpi, int col, SCIP_RATIONAL scaleval)

Data Accessing Methods
SCIP_RETCODE	SCIPlpiExactGetNRows (SCIP_LPIEXACT lpi, int nrows)
SCIP_RETCODE	SCIPlpiExactGetNCols (SCIP_LPIEXACT lpi, int ncols)
SCIP_RETCODE	SCIPlpiExactGetObjsen (SCIP_LPIEXACT lpi, SCIP_OBJSEN objsen)
SCIP_RETCODE	SCIPlpiExactGetNNonz (SCIP_LPIEXACT lpi, int nnonz)
SCIP_RETCODE	SCIPlpiExactGetCols (SCIP_LPIEXACT lpi, int firstcol, int lastcol, SCIP_RATIONAL lb, SCIP_RATIONAL ub, int nnonz, int beg, int ind, SCIP_RATIONAL **val)
SCIP_RETCODE	SCIPlpiExactGetRows (SCIP_LPIEXACT lpi, int firstrow, int lastrow, SCIP_RATIONAL lhs, SCIP_RATIONAL rhs, int nnonz, int beg, int ind, SCIP_RATIONAL **val)
SCIP_RETCODE	SCIPlpiExactGetColNames (SCIP_LPIEXACT lpi, int firstcol, int lastcol, char colnames, char namestorage, int namestoragesize, int *storageleft)
SCIP_RETCODE	SCIPlpiExactGetRowNames (SCIP_LPIEXACT lpi, int firstrow, int lastrow, char rownames, char namestorage, int namestoragesize, int *storageleft)
SCIP_RETCODE	SCIPlpiExactGetObj (SCIP_LPIEXACT lpi, int firstcol, int lastcol, SCIP_RATIONAL *vals)
SCIP_RETCODE	SCIPlpiExactGetBounds (SCIP_LPIEXACT lpi, int firstcol, int lastcol, SCIP_RATIONAL lbs, SCIP_RATIONAL *ubs)
SCIP_RETCODE	SCIPlpiExactGetSides (SCIP_LPIEXACT lpi, int firstrow, int lastrow, SCIP_RATIONAL lhss, SCIP_RATIONAL *rhss)
SCIP_RETCODE	SCIPlpiExactGetCoef (SCIP_LPIEXACT lpi, int row, int col, SCIP_RATIONAL val)

Solving Methods
SCIP_RETCODE	SCIPlpiExactSolvePrimal (SCIP_LPIEXACT *lpi)
SCIP_RETCODE	SCIPlpiExactSolveDual (SCIP_LPIEXACT *lpi)
SCIP_RETCODE	SCIPlpiExactSolveBarrier (SCIP_LPIEXACT *lpi, SCIP_Bool crossover)
SCIP_RETCODE	SCIPlpiExactStartStrongbranch (SCIP_LPIEXACT *lpi)
SCIP_RETCODE	SCIPlpiExactEndStrongbranch (SCIP_LPIEXACT *lpi)
SCIP_RETCODE	SCIPlpiExactStrongbranch (SCIP_LPIEXACT lpi, int col, const SCIP_RATIONAL psol, int itlim, SCIP_RATIONAL down, SCIP_RATIONAL up, SCIP_Bool downvalid, SCIP_Bool upvalid, int *iter)

Solution Information Methods
SCIP_Bool	SCIPlpiExactWasSolved (SCIP_LPIEXACT *lpi)
SCIP_RETCODE	SCIPlpiExactGetSolFeasibility (SCIP_LPIEXACT lpi, SCIP_Bool primalfeasible, SCIP_Bool *dualfeasible)
SCIP_Bool	SCIPlpiExactExistsPrimalRay (SCIP_LPIEXACT *lpi)
SCIP_Bool	SCIPlpiExactHasPrimalRay (SCIP_LPIEXACT *lpi)
SCIP_Bool	SCIPlpiExactIsPrimalUnbounded (SCIP_LPIEXACT *lpi)
SCIP_Bool	SCIPlpiExactIsPrimalInfeasible (SCIP_LPIEXACT *lpi)
SCIP_Bool	SCIPlpiExactIsPrimalFeasible (SCIP_LPIEXACT *lpi)
SCIP_Bool	SCIPlpiExactExistsDualRay (SCIP_LPIEXACT *lpi)
SCIP_Bool	SCIPlpiExactHasDualRay (SCIP_LPIEXACT *lpi)
SCIP_Bool	SCIPlpiExactIsDualUnbounded (SCIP_LPIEXACT *lpi)
SCIP_Bool	SCIPlpiExactIsDualInfeasible (SCIP_LPIEXACT *lpi)
SCIP_Bool	SCIPlpiExactIsDualFeasible (SCIP_LPIEXACT *lpi)
SCIP_Bool	SCIPlpiExactIsOptimal (SCIP_LPIEXACT *lpi)
SCIP_Bool	SCIPlpiExactIsStable (SCIP_LPIEXACT *lpi)
SCIP_Bool	SCIPlpiExactIsObjlimExc (SCIP_LPIEXACT *lpi)
SCIP_Bool	SCIPlpiExactIsIterlimExc (SCIP_LPIEXACT *lpi)
SCIP_Bool	SCIPlpiExactIsTimelimExc (SCIP_LPIEXACT *lpi)
int	SCIPlpiExactGetInternalStatus (SCIP_LPIEXACT *lpi)
SCIP_RETCODE	SCIPlpiExactIgnoreInstability (SCIP_LPIEXACT lpi, SCIP_Bool success)
SCIP_RETCODE	SCIPlpiExactGetObjval (SCIP_LPIEXACT lpi, SCIP_RATIONAL objval)
SCIP_RETCODE	SCIPlpiExactGetSol (SCIP_LPIEXACT lpi, SCIP_RATIONAL objval, SCIP_RATIONAL primsol, SCIP_RATIONAL dualsol, SCIP_RATIONAL activity, SCIP_RATIONAL redcost)
SCIP_RETCODE	SCIPlpiExactGetPrimalRay (SCIP_LPIEXACT lpi, SCIP_RATIONAL *ray)
SCIP_RETCODE	SCIPlpiExactGetDualfarkas (SCIP_LPIEXACT lpi, SCIP_RATIONAL *dualfarkas)
SCIP_RETCODE	SCIPlpiExactGetIterations (SCIP_LPIEXACT lpi, int iterations)

LP Basis Methods
SCIP_RETCODE	SCIPlpiExactGetBase (SCIP_LPIEXACT lpi, int cstat, int *rstat)
SCIP_RETCODE	SCIPlpiExactSetBase (SCIP_LPIEXACT lpi, int cstat, int *rstat)
SCIP_RETCODE	SCIPlpiExactGetBasisInd (SCIP_LPIEXACT lpi, int bind)
SCIP_RETCODE	SCIPlpiExactGetBInvRow (SCIP_LPIEXACT lpi, int r, SCIP_RATIONAL coef, int inds, int *ninds)
SCIP_RETCODE	SCIPlpiExactGetBInvCol (SCIP_LPIEXACT lpi, int c, SCIP_RATIONAL coef, int inds, int *ninds)
SCIP_RETCODE	SCIPlpiExactGetBInvARow (SCIP_LPIEXACT lpi, int r, SCIP_RATIONAL binvrow, SCIP_RATIONAL coef, int inds, int *ninds)
SCIP_RETCODE	SCIPlpiExactGetBInvACol (SCIP_LPIEXACT lpi, int c, SCIP_RATIONAL coef, int inds, int *ninds)

LPi State Methods
SCIP_RETCODE	SCIPlpiExactGetState (SCIP_LPIEXACT lpi, BMS_BLKMEM blkmem, SCIP_LPISTATE **lpistate)
SCIP_RETCODE	SCIPlpiExactSetState (SCIP_LPIEXACT lpi, BMS_BLKMEM blkmem, SCIP_LPISTATE *lpistate)
SCIP_RETCODE	SCIPlpiExactClearState (SCIP_LPIEXACT *lpi)
SCIP_RETCODE	SCIPlpiExactFreeState (SCIP_LPIEXACT lpi, BMS_BLKMEM blkmem, SCIP_LPISTATE **lpistate)
SCIP_Bool	SCIPlpiExactHasStateBasis (SCIP_LPIEXACT lpi, SCIP_LPISTATE lpistate)
SCIP_RETCODE	SCIPlpiExactReadState (SCIP_LPIEXACT lpi, const char fname)
SCIP_RETCODE	SCIPlpiExactWriteState (SCIP_LPIEXACT lpi, const char fname)
SCIP_RETCODE	SCIPlpiExactStateDualFeasible (SCIP_LPIEXACT lpi, BMS_BLKMEM blkmem, SCIP_LPISTATE lpistate, SCIP_Bool useprestep, SCIP_Real primalsol, SCIP_Real dualsol, SCIP_Bool result, SCIP_RATIONAL **dualobjval)

LPi Pricing Norms Methods
SCIP_RETCODE	SCIPlpiExactGetNorms (SCIP_LPIEXACT lpi, BMS_BLKMEM blkmem, SCIP_LPINORMS **lpinorms)
SCIP_RETCODE	SCIPlpiExactSetNorms (SCIP_LPIEXACT lpi, BMS_BLKMEM blkmem, const SCIP_LPINORMS *lpinorms)
SCIP_RETCODE	SCIPlpiExactFreeNorms (SCIP_LPIEXACT lpi, BMS_BLKMEM blkmem, SCIP_LPINORMS **lpinorms)

Parameter Methods
SCIP_RETCODE	SCIPlpiExactGetIntpar (SCIP_LPIEXACT lpi, SCIP_LPPARAM type, int ival)
SCIP_RETCODE	SCIPlpiExactSetIntpar (SCIP_LPIEXACT *lpi, SCIP_LPPARAM type, int ival)
SCIP_RETCODE	SCIPlpiExactGetRealpar (SCIP_LPIEXACT lpi, SCIP_LPPARAM type, SCIP_Real dval)
SCIP_RETCODE	SCIPlpiExactSetRealpar (SCIP_LPIEXACT *lpi, SCIP_LPPARAM type, SCIP_Real dval)

Numerical Methods
void	SCIPlpiExactPosInfinity (SCIP_LPIEXACT lpi, SCIP_RATIONAL infval)
SCIP_Bool	SCIPlpiExactIsPosInfinity (SCIP_LPIEXACT lpi, SCIP_RATIONAL val)
void	SCIPlpiExactNegInfinity (SCIP_LPIEXACT lpi, SCIP_RATIONAL infval)
SCIP_Bool	SCIPlpiExactIsNegInfinity (SCIP_LPIEXACT lpi, SCIP_RATIONAL val)
SCIP_Real	SCIPlpiExactInfinity (SCIP_LPIEXACT *lpi)
SCIP_Bool	SCIPlpiExactIsInfinity (SCIP_LPIEXACT *lpi, SCIP_Real val)

File Interface Methods
SCIP_RETCODE	SCIPlpiExactReadLP (SCIP_LPIEXACT lpi, const char fname)
SCIP_RETCODE	SCIPlpiExactWriteLP (SCIP_LPIEXACT lpi, const char fname)

Exact LU decomposition solver interface
SCIP_RETCODE	SCIPlpiExactCreateFactor (SCIP_LPIEXACT lpi, int dim, int cbeg, int clen, int cindx, SCIP_RATIONAL *ccoef)
SCIP_RETCODE	SCIPlpiExactFactorSolve (SCIP_LPIEXACT lpi, int dim, SCIP_RATIONAL sol, SCIP_RATIONAL *rhs)

Miscellaneous Methods
SCIP_RETCODE	SCIPlpiExactSetIntegralityInformation (SCIP_LPIEXACT lpi, int ncols, int intInfo)
SCIP_Bool	SCIPlpiExactHasPrimalSolve (void)
SCIP_Bool	SCIPlpiExactHasDualSolve (void)
SCIP_Bool	SCIPlpiExactHasBarrierSolve (void)

Modification Methods
SCIP_RETCODE	SCIPlpiDelColset (SCIP_LPIEXACT lpi, int dstat)

Function Documentation

◆ SCIPlpiExactGetSolverName()

const char * SCIPlpiExactGetSolverName ( void )

gets name and version of LP solver

Definition at line 92 of file lpiexact_none.c.

References LPINAME, SCIPdebugMessage, and spxname.

Referenced by doScipCreate().

◆ SCIPlpiExactGetSolverDesc()

const char * SCIPlpiExactGetSolverDesc ( void )

gets description of LP solver (developer, webpage, ...)

Definition at line 100 of file lpiexact_none.c.

References spxdesc.

Referenced by doScipCreate().

◆ SCIPlpiExactGetExternalCodeName()

const char * SCIPlpiExactGetExternalCodeName ( void )

gets name and version of external package required for LP solver

Definition at line 420 of file lpiexact_qsoex.c.

◆ SCIPlpiExactPrintInfo()

void SCIPlpiExactPrintInfo ( SCIP_LPIEXACT * lpi )

prints additional lpiexact internal info

Parameters

lpi	LP interface structure

◆ SCIPlpiExactGetExternalCodeDesc()

const char * SCIPlpiExactGetExternalCodeDesc ( void )

gets description of external package required for LP solver (developer, webpage, ...)

Definition at line 434 of file lpiexact_qsoex.c.

◆ SCIPlpiExactGetSolverPointer()

void * SCIPlpiExactGetSolverPointer ( SCIP_LPIEXACT * lpi )

gets pointer for LP solver - use only with great care

The behavior of this function depends on the solver and its use is therefore only recommended if you really know what you are doing. In general, it returns a pointer to the LP solver object.

gets pointer for LP solver - use only with great care

Parameters

lpi	pointer to an LP interface structure

Definition at line 108 of file lpiexact_none.c.

References NULL, and SCIP_LPiExact::spx.

◆ SCIPlpiExactStart()

void SCIPlpiExactStart ( void )

calls initializator of LP solver; this is mainly needed for defining constants in extended and rational precision

◆ SCIPlpiExactEnd()

void SCIPlpiExactEnd ( void )

calls deinitializator of LP solver; this is needed for freeing all internal data of the solver, like constants in extended and rational precision

References obj.

◆ SCIPlpiExactCreate()

SCIP_RETCODE SCIPlpiExactCreate	(	SCIP_LPIEXACT **	lpi,
		SCIP_MESSAGEHDLR *	messagehdlr,
		const char *	name,
		SCIP_OBJSEN	objsen )

creates an LP problem object

Parameters

lpi	pointer to an LP interface structure
messagehdlr	message handler to use for printing messages, or NULL
name	problem name
objsen	objective sense

Definition at line 126 of file lpiexact_none.c.

References assert(), BMSallocMemory, BMSallocMemoryCPP, FALSE, invalidateSolution(), NULL, SCIP_ALLOC, SCIP_CALL, SCIP_LPPAR_PRICING, SCIP_OKAY, SCIP_PRICING_LPIDEFAULT, SCIPdebugMessage, SCIPlpiExactChgObjsen(), SCIPlpiExactSetIntpar(), SOPLEX_TRY, and SOPLEX_VERBLEVEL.

Referenced by SCIPlpExactCreate().

◆ SCIPlpiExactFree()

SCIP_RETCODE SCIPlpiExactFree ( SCIP_LPIEXACT ** lpi )

deletes an LP problem object

Parameters

lpi	pointer to an LP interface structure

Definition at line 147 of file lpiexact_none.c.

References assert(), BMSfreeMemory, BMSfreeMemoryArrayNull, NULL, SCIP_OKAY, and SCIPdebugMessage.

Referenced by SCIPlpExactFree(), and SCIPlpExactProjectShiftFreeLPIExact().

◆ SCIPlpiExactLoadColLP()

SCIP_RETCODE SCIPlpiExactLoadColLP	(	SCIP_LPIEXACT *	lpi,
		SCIP_OBJSEN	objsen,
		int	ncols,
		SCIP_RATIONAL **	obj,
		SCIP_RATIONAL **	lb,
		SCIP_RATIONAL **	ub,
		char **	colnames,
		int	nrows,
		SCIP_RATIONAL **	lhs,
		SCIP_RATIONAL **	rhs,
		char **	rownames,
		int	nnonz,
		int *	beg,
		int *	ind,
		SCIP_RATIONAL **	val )

copies LP data with column matrix into LP solver

Parameters

lpi	LP interface structure
objsen	objective sense
ncols	number of columns
obj	objective function values of columns
lb	lower bounds of columns
ub	upper bounds of columns
colnames	column names, or NULL
nrows	number of rows
lhs	left hand sides of rows
rhs	right hand sides of rows
rownames	row names, or NULL
nnonz	number of nonzero elements in the constraint matrix
beg	start index of each column in ind- and val-array
ind	row indices of constraint matrix entries
val	values of constraint matrix entries

Definition at line 170 of file lpiexact_none.c.

References assert(), i, invalidateSolution(), SCIP_LPiExact::messagehdlr, SCIP_LPiExact::ncols, SCIP_LPiExact::nrows, NULL, obj, SPxexSCIP::preStrongbranchingBasisFreed(), SCIP_CALL, SCIP_LPERROR, SCIP_OBJSEN_MINIMIZE, SCIP_OKAY, SCIPdebugMessage, SCIPlpiExactAddCols(), SCIPmessagePrintWarning(), SCIPrationalIsZero(), SCIP_LPiExact::spx, SpxRSetRat(), and x.

◆ SCIPlpiExactAddCols()

SCIP_RETCODE SCIPlpiExactAddCols	(	SCIP_LPIEXACT *	lpi,
		int	ncols,
		SCIP_RATIONAL **	obj,
		SCIP_RATIONAL **	lb,
		SCIP_RATIONAL **	ub,
		char **	colnames,
		int	nnonz,
		int *	beg,
		int *	ind,
		SCIP_RATIONAL **	val )

adds columns to the LP

Parameters

lpi	LP interface structure
ncols	number of columns to be added
obj	objective function values of new columns
lb	lower bounds of new columns
ub	upper bounds of new columns
colnames	column names, or NULL
nnonz	number of nonzero elements to be added to the constraint matrix
beg	start index of each column in ind- and val-array, or NULL if nnonz == 0
ind	row indices of constraint matrix entries, or NULL if nnonz == 0
val	values of constraint matrix entries, or NULL if nnonz == 0

Definition at line 215 of file lpiexact_none.c.

References assert(), i, invalidateSolution(), SCIP_LPiExact::messagehdlr, SCIP_LPiExact::ncols, NULL, obj, SPxexSCIP::preStrongbranchingBasisFreed(), SCIP_LPERROR, SCIP_OKAY, SCIPdebugMessage, SCIPmessagePrintWarning(), SCIPrationalIsZero(), SCIP_LPiExact::spx, SpxRSetRat(), and x.

Referenced by lpExactFlushAddCols(), and SCIPlpiExactLoadColLP().

◆ SCIPlpiExactDelCols()

SCIP_RETCODE SCIPlpiExactDelCols	(	SCIP_LPIEXACT *	lpi,
		int	firstcol,
		int	lastcol )

deletes all columns in the given range from LP

Parameters

lpi	LP interface structure
firstcol	first column to be deleted
lastcol	last column to be deleted

Definition at line 245 of file lpiexact_none.c.

References assert(), invalidateSolution(), SCIP_LPiExact::messagehdlr, SCIP_LPiExact::ncols, NULL, SPxexSCIP::preStrongbranchingBasisFreed(), SCIP_OKAY, SCIPdebugMessage, SOPLEX_TRY, and SCIP_LPiExact::spx.

Referenced by lpExactFlushDelCols(), and SCIPlpExactProjectShiftFreeLPIExact().

◆ SCIPlpiExactDelColset()

SCIP_RETCODE SCIPlpiExactDelColset	(	SCIP_LPIEXACT *	lpi,
		int *	dstat )

deletes columns from SCIP_LP; the new position of a column must not be greater that its old position

Parameters

lpi	LP interface structure
dstat	deletion status of columns input: 1 if column should be deleted, 0 if not output: new position of column, -1 if column was deleted

References obj.

◆ SCIPlpiExactAddRows()

SCIP_RETCODE SCIPlpiExactAddRows	(	SCIP_LPIEXACT *	lpi,
		int	nrows,
		SCIP_RATIONAL **	lhs,
		SCIP_RATIONAL **	rhs,
		char **	rownames,
		int	nnonz,
		int *	beg,
		int *	ind,
		SCIP_RATIONAL **	val )

adds rows to the LP

Parameters

lpi	LP interface structure
nrows	number of rows to be added
lhs	left hand sides of new rows
rhs	right hand sides of new rows
rownames	row names, or NULL
nnonz	number of nonzero elements to be added to the constraint matrix
beg	start index of each row in ind- and val-array, or NULL if nnonz == 0
ind	column indices of constraint matrix entries, or NULL if nnonz == 0
val	values of constraint matrix entries, or NULL if nnonz == 0

Definition at line 261 of file lpiexact_none.c.

References assert(), i, invalidateSolution(), SCIP_LPiExact::messagehdlr, SCIP_LPiExact::nrows, NULL, SPxexSCIP::preStrongbranchingBasisFreed(), SCIP_LPERROR, SCIP_OKAY, SCIPdebugMessage, SCIPmessagePrintWarning(), SCIPrationalIsZero(), SCIP_LPiExact::spx, SpxRSetRat(), and x.

Referenced by lpExactFlushAddRows().

◆ SCIPlpiExactDelRows()

SCIP_RETCODE SCIPlpiExactDelRows	(	SCIP_LPIEXACT *	lpi,
		int	firstrow,
		int	lastrow )

deletes all rows in the given range from LP

Parameters

lpi	LP interface structure
firstrow	first row to be deleted
lastrow	last row to be deleted

Definition at line 287 of file lpiexact_none.c.

References assert(), invalidateSolution(), SCIP_LPiExact::messagehdlr, SCIP_LPiExact::nrows, NULL, SPxexSCIP::preStrongbranchingBasisFreed(), SCIP_OKAY, SCIPdebugMessage, SOPLEX_TRY, and SCIP_LPiExact::spx.

Referenced by lpExactFlushDelRows(), and SCIPlpExactProjectShiftFreeLPIExact().

◆ SCIPlpiExactDelRowset()

SCIP_RETCODE SCIPlpiExactDelRowset	(	SCIP_LPIEXACT *	lpi,
		int *	dstat )

deletes rows from SCIP_LP; the new position of a row must not be greater that its old position

Parameters

lpi	LP interface structure
dstat	deletion status of rows input: 1 if row should be deleted, 0 if not output: new position of row, -1 if row was deleted

Definition at line 303 of file lpiexact_none.c.

References assert(), i, invalidateSolution(), SCIP_LPiExact::messagehdlr, SCIP_LPiExact::nrows, NULL, SPxexSCIP::preStrongbranchingBasisFreed(), SCIP_OKAY, SCIPdebugMessage, SOPLEX_TRY, and SCIP_LPiExact::spx.

Referenced by SCIPlpExactDelRowset().

◆ SCIPlpiExactClear()

SCIP_RETCODE SCIPlpiExactClear ( SCIP_LPIEXACT * lpi )

clears the whole LP

Parameters

lpi	LP interface structure

Definition at line 334 of file lpiexact_none.c.

References assert(), invalidateSolution(), SCIP_LPiExact::messagehdlr, SCIP_LPiExact::ncols, SCIP_LPiExact::nrows, NULL, SPxexSCIP::preStrongbranchingBasisFreed(), SCIP_OKAY, SCIPdebugMessage, SOPLEX_TRY, and SCIP_LPiExact::spx.

Referenced by SCIPlpExactProjectShiftFreeLPIExact().

◆ SCIPlpiExactChgBounds()

SCIP_RETCODE SCIPlpiExactChgBounds	(	SCIP_LPIEXACT *	lpi,
		int	ncols,
		int *	ind,
		SCIP_RATIONAL **	lb,
		SCIP_RATIONAL **	ub )

changes lower and upper bounds of columns

Parameters

lpi	LP interface structure
ncols	number of columns to change bounds for
ind	column indices or NULL if ncols is zero
lb	values for the new lower bounds or NULL if ncols is zero
ub	values for the new upper bounds or NULL if ncols is zero

Definition at line 349 of file lpiexact_none.c.

References assert(), i, invalidateSolution(), SCIP_LPiExact::messagehdlr, NULL, SPxexSCIP::preStrongbranchingBasisFreed(), SCIP_LPERROR, SCIP_OKAY, SCIPdebugMessage, SCIPerrorMessage, SCIPmessagePrintWarning(), SCIPrationalIsInfinity(), SCIPrationalIsNegInfinity(), SCIP_LPiExact::spx, SpxRSetRat(), and x.

Referenced by lpExactFlushChgCols().

◆ SCIPlpiExactChgSides()

SCIP_RETCODE SCIPlpiExactChgSides	(	SCIP_LPIEXACT *	lpi,
		int	nrows,
		int *	ind,
		SCIP_RATIONAL **	lhs,
		SCIP_RATIONAL **	rhs )

changes left and right hand sides of rows

Parameters

lpi	LP interface structure
nrows	number of rows to change sides for
ind	row indices
lhs	new values for left hand sides
rhs	new values for right hand sides

Definition at line 362 of file lpiexact_none.c.

References assert(), i, invalidateSolution(), SCIP_LPiExact::messagehdlr, NULL, SPxexSCIP::preStrongbranchingBasisFreed(), SCIP_LPERROR, SCIP_OKAY, SCIPdebugMessage, SCIPmessagePrintWarning(), SCIP_LPiExact::spx, SpxRSetRat(), and x.

Referenced by lpExactFlushChgRows().

◆ SCIPlpiExactChgCoef()

SCIP_RETCODE SCIPlpiExactChgCoef	(	SCIP_LPIEXACT *	lpi,
		int	row,
		int	col,
		SCIP_RATIONAL *	newval )

changes a single coefficient

Parameters

lpi	LP interface structure
row	row number of coefficient to change
col	column number of coefficient to change
newval	new value of coefficient

Definition at line 379 of file lpiexact_none.c.

References assert(), invalidateSolution(), SCIP_LPiExact::messagehdlr, NULL, SPxexSCIP::preStrongbranchingBasisFreed(), SCIP_OKAY, SCIPdebugMessage, SOPLEX_TRY, SCIP_LPiExact::spx, and SpxRSetRat().

◆ SCIPlpiExactChgObjsen()

SCIP_RETCODE SCIPlpiExactChgObjsen	(	SCIP_LPIEXACT *	lpi,
		SCIP_OBJSEN	objsen )

changes the objective sense

Parameters

lpi	LP interface structure
objsen	new objective sense

Definition at line 391 of file lpiexact_none.c.

References assert(), invalidateSolution(), SCIP_LPiExact::messagehdlr, NULL, SPxexSCIP::preStrongbranchingBasisFreed(), SCIP_OBJSEN_MINIMIZE, SCIP_OKAY, SCIPdebugMessage, SOPLEX_TRY, and SCIP_LPiExact::spx.

Referenced by SCIPlpiExactCreate().

◆ SCIPlpiExactChgObj()

SCIP_RETCODE SCIPlpiExactChgObj	(	SCIP_LPIEXACT *	lpi,
		int	ncols,
		int *	ind,
		SCIP_RATIONAL **	obj )

changes objective values of columns in the LP

Parameters

lpi	LP interface structure
ncols	number of columns to change objective value for
ind	column indices to change objective value for
obj	new objective values for columns

Definition at line 401 of file lpiexact_none.c.

References assert(), i, invalidateSolution(), SCIP_LPiExact::messagehdlr, NULL, obj, SPxexSCIP::preStrongbranchingBasisFreed(), SCIP_LPERROR, SCIP_OKAY, SCIPdebugMessage, SCIPmessagePrintWarning(), SCIP_LPiExact::spx, SpxRSetRat(), and x.

Referenced by lpExactFlushChgCols().

◆ SCIPlpiExactScaleRow()

SCIP_RETCODE SCIPlpiExactScaleRow	(	SCIP_LPIEXACT *	lpi,
		int	row,
		SCIP_RATIONAL *	scaleval )

multiplies a row with a non-zero scalar; for negative scalars, the row's sense is switched accordingly

Parameters

lpi	LP interface structure
row	row number to scale
scaleval	scaling multiplier

◆ SCIPlpiExactScaleCol()

SCIP_RETCODE SCIPlpiExactScaleCol	(	SCIP_LPIEXACT *	lpi,
		int	col,
		SCIP_RATIONAL *	scaleval )

multiplies a column with a non-zero scalar; the objective value is multiplied with the scalar, and the bounds are divided by the scalar; for negative scalars, the column's bounds are switched

Parameters

lpi	LP interface structure
col	column number to scale
scaleval	scaling multiplier

References SCIP_Bool.

◆ SCIPlpiExactGetNRows()

SCIP_RETCODE SCIPlpiExactGetNRows	(	SCIP_LPIEXACT *	lpi,
		int *	nrows )

gets the number of rows in the LP

Parameters

lpi	LP interface structure
nrows	pointer to store the number of rows

Definition at line 423 of file lpiexact_none.c.

References assert(), SCIP_LPiExact::nrows, NULL, SCIP_OKAY, SCIPdebugMessage, and SCIP_LPiExact::spx.

Referenced by SCIPlpExactFlush(), SCIPlpExactProjectShiftFreeLPIExact(), and SCIPlpiExactSetBase().

◆ SCIPlpiExactGetNCols()

SCIP_RETCODE SCIPlpiExactGetNCols	(	SCIP_LPIEXACT *	lpi,
		int *	ncols )

gets the number of columns in the LP

Parameters

lpi	LP interface structure
ncols	pointer to store the number of cols

Definition at line 438 of file lpiexact_none.c.

References assert(), SCIP_LPiExact::ncols, NULL, SCIP_OKAY, SCIPdebugMessage, and SCIP_LPiExact::spx.

Referenced by SCIPlpExactFlush(), SCIPlpExactProjectShiftFreeLPIExact(), and SCIPlpiExactSetBase().

◆ SCIPlpiExactGetObjsen()

SCIP_RETCODE SCIPlpiExactGetObjsen	(	SCIP_LPIEXACT *	lpi,
		SCIP_OBJSEN *	objsen )

gets the objective sense of the LP

gets objective sense of the LP

Parameters

lpi	LP interface structure
objsen	pointer to store objective sense

Definition at line 545 of file lpiexact_none.c.

References assert(), errorMessage(), NULL, SCIP_OBJSEN_MAXIMIZE, SCIP_OBJSEN_MINIMIZE, SCIP_OKAY, SCIP_PLUGINNOTFOUND, SCIPdebugMessage, and SCIP_LPiExact::spx.

◆ SCIPlpiExactGetNNonz()

SCIP_RETCODE SCIPlpiExactGetNNonz	(	SCIP_LPIEXACT *	lpi,
		int *	nnonz )

gets the number of nonzero elements in the LP constraint matrix

Parameters

lpi	LP interface structure
nnonz	pointer to store the number of nonzeros

Definition at line 453 of file lpiexact_none.c.

References assert(), errorMessage(), i, NULL, SCIP_OKAY, SCIP_PLUGINNOTFOUND, SCIPdebugMessage, and SCIP_LPiExact::spx.

◆ SCIPlpiExactGetCols()

SCIP_RETCODE SCIPlpiExactGetCols	(	SCIP_LPIEXACT *	lpi,
		int	firstcol,
		int	lastcol,
		SCIP_RATIONAL **	lb,
		SCIP_RATIONAL **	ub,
		int *	nnonz,
		int *	beg,
		int *	ind,
		SCIP_RATIONAL **	val )

gets columns from LP problem object; the arrays have to be large enough to store all values; Either both, lb and ub, have to be NULL, or both have to be non-NULL, either nnonz, beg, ind, and val have to be NULL, or all of them have to be non-NULL.

gets columns from LP problem object; the arrays have to be large enough to store all values Either both, lb and ub, have to be NULL, or both have to be non-NULL, either nnonz, beg, ind, and val have to be NULL, or all of them have to be non-NULL.

Parameters

lpi	LP interface structure
firstcol	first column to get from LP
lastcol	last column to get from LP
lb	buffer to store the lower bound vector, or NULL
ub	buffer to store the upper bound vector, or NULL
nnonz	pointer to store the number of nonzero elements returned, or NULL
beg	buffer to store start index of each column in ind- and val-array, or NULL
ind	buffer to store row indices of constraint matrix entries, or NULL
val	buffer to store values of constraint matrix entries, or NULL

Definition at line 468 of file lpiexact_none.c.

References assert(), errorMessage(), i, NULL, RsetSpxR(), SCIP_OKAY, SCIP_PLUGINNOTFOUND, SCIPdebugMessage, and SCIP_LPiExact::spx.

◆ SCIPlpiExactGetRows()

SCIP_RETCODE SCIPlpiExactGetRows	(	SCIP_LPIEXACT *	lpi,
		int	firstrow,
		int	lastrow,
		SCIP_RATIONAL **	lhs,
		SCIP_RATIONAL **	rhs,
		int *	nnonz,
		int *	beg,
		int *	ind,
		SCIP_RATIONAL **	val )

gets rows from LP problem object; the arrays have to be large enough to store all values. Either both, lhs and rhs, have to be NULL, or both have to be non-NULL, either nnonz, beg, ind, and val have to be NULL, or all of them have to be non-NULL.

Parameters

lpi	LP interface structure
firstrow	first row to get from LP
lastrow	last row to get from LP
lhs	buffer to store left hand side vector, or NULL
rhs	buffer to store right hand side vector, or NULL
nnonz	pointer to store the number of nonzero elements returned, or NULL
beg	buffer to store start index of each row in ind- and val-array, or NULL
ind	buffer to store column indices of constraint matrix entries, or NULL
val	buffer to store values of constraint matrix entries, or NULL

Definition at line 488 of file lpiexact_none.c.

References assert(), errorMessage(), FALSE, i, NULL, RsetSpxR(), SCIP_OKAY, SCIP_PLUGINNOTFOUND, SCIPdebugMessage, and SCIP_LPiExact::spx.

◆ SCIPlpiExactGetColNames()

SCIP_RETCODE SCIPlpiExactGetColNames	(	SCIP_LPIEXACT *	lpi,
		int	firstcol,
		int	lastcol,
		char **	colnames,
		char *	namestorage,
		int	namestoragesize,
		int *	storageleft )

gets column names

Parameters

lpi	LP interface structure
firstcol	first column to get name from LP
lastcol	last column to get name from LP
colnames	pointers to column names (of size at least lastcol-firstcol+1) or NULL if namestoragesize is zero
namestorage	storage for col names or NULL if namestoragesize is zero
namestoragesize	size of namestorage (if 0, storageleft returns the storage needed)
storageleft	amount of storage left (if < 0 the namestorage was not big enough) or NULL if namestoragesize is zero

Definition at line 505 of file lpiexact_none.c.

References assert(), errorMessage(), NULL, SCIP_NOTIMPLEMENTED, SCIP_PLUGINNOTFOUND, SCIPdebugMessage, SCIPerrorMessage, and SCIP_LPiExact::spx.

◆ SCIPlpiExactGetRowNames()

SCIP_RETCODE SCIPlpiExactGetRowNames	(	SCIP_LPIEXACT *	lpi,
		int	firstrow,
		int	lastrow,
		char **	rownames,
		char *	namestorage,
		int	namestoragesize,
		int *	storageleft )

gets row names

Parameters

lpi	LP interface structure
firstrow	first row to get name from LP
lastrow	last row to get name from LP
rownames	pointers to row names (of size at least lastrow-firstrow+1) or NULL if namestoragesize is zero
namestorage	storage for row names or NULL if namestoragesize is zero
namestoragesize	size of namestorage (if 0, -storageleft returns the storage needed)
storageleft	amount of storage left (if < 0 the namestorage was not big enough) or NULL if namestoragesize is zero

Definition at line 525 of file lpiexact_none.c.

References assert(), errorMessage(), NULL, SCIP_NOTIMPLEMENTED, SCIP_PLUGINNOTFOUND, SCIPdebugMessage, SCIPerrorMessage, and SCIP_LPiExact::spx.

◆ SCIPlpiExactGetObj()

SCIP_RETCODE SCIPlpiExactGetObj	(	SCIP_LPIEXACT *	lpi,
		int	firstcol,
		int	lastcol,
		SCIP_RATIONAL **	vals )

gets objective coefficients from LP problem object

Parameters

lpi	LP interface structure
firstcol	first column to get objective coefficient for
lastcol	last column to get objective coefficient for
vals	array to store objective coefficients

Definition at line 555 of file lpiexact_none.c.

References assert(), errorMessage(), i, NULL, RsetSpxR(), SCIP_OKAY, SCIP_PLUGINNOTFOUND, SCIPdebugMessage, and SCIP_LPiExact::spx.

Referenced by lpExactFlushChgCols().

◆ SCIPlpiExactGetBounds()

SCIP_RETCODE SCIPlpiExactGetBounds	(	SCIP_LPIEXACT *	lpi,
		int	firstcol,
		int	lastcol,
		SCIP_RATIONAL **	lbs,
		SCIP_RATIONAL **	ubs )

gets current bounds from LP problem object

Parameters

lpi	LP interface structure
firstcol	first column to get objective value for
lastcol	last column to get objective value for
lbs	array to store lower bound values, or NULL
ubs	array to store upper bound values, or NULL

Definition at line 570 of file lpiexact_none.c.

References assert(), errorMessage(), i, NULL, RsetSpxR(), SCIP_OKAY, SCIP_PLUGINNOTFOUND, SCIPdebugMessage, and SCIP_LPiExact::spx.

Referenced by lpExactFlushChgCols().

◆ SCIPlpiExactGetSides()

SCIP_RETCODE SCIPlpiExactGetSides	(	SCIP_LPIEXACT *	lpi,
		int	firstrow,
		int	lastrow,
		SCIP_RATIONAL **	lhss,
		SCIP_RATIONAL **	rhss )

gets current row sides from LP problem object

Parameters

lpi	LP interface structure
firstrow	first row to get sides for
lastrow	last row to get sides for
lhss	array to store left hand side values, or NULL
rhss	array to store right hand side values, or NULL

Definition at line 585 of file lpiexact_none.c.

References assert(), errorMessage(), i, NULL, RsetSpxR(), SCIP_OKAY, SCIP_PLUGINNOTFOUND, SCIPdebugMessage, and SCIP_LPiExact::spx.

Referenced by lpExactFlushChgRows().

◆ SCIPlpiExactGetCoef()

SCIP_RETCODE SCIPlpiExactGetCoef	(	SCIP_LPIEXACT *	lpi,
		int	row,
		int	col,
		SCIP_RATIONAL *	val )

gets a single coefficient

Parameters

lpi	LP interface structure
row	row number of coefficient
col	column number of coefficient
val	pointer to store the value of the coefficient

Definition at line 600 of file lpiexact_none.c.

References assert(), errorMessage(), NULL, RsetSpxR(), SCIP_OKAY, SCIP_PLUGINNOTFOUND, SCIPdebugMessage, and SCIP_LPiExact::spx.

◆ SCIPlpiExactSolvePrimal()

SCIP_RETCODE SCIPlpiExactSolvePrimal ( SCIP_LPIEXACT * lpi )

calls primal simplex to solve the LP

Parameters

lpi	LP interface structure

Definition at line 624 of file lpiexact_none.c.

References assert(), errorMessage(), NULL, SCIP_PLUGINNOTFOUND, SCIPdebugMessage, SCIP_LPiExact::spx, and spxSolve().

◆ SCIPlpiExactSolveDual()

SCIP_RETCODE SCIPlpiExactSolveDual ( SCIP_LPIEXACT * lpi )

calls dual simplex to solve the LP

Parameters

lpi	LP interface structure

Definition at line 634 of file lpiexact_none.c.

References assert(), errorMessage(), NULL, SCIP_PLUGINNOTFOUND, SCIPdebugMessage, SCIP_LPiExact::spx, and spxSolve().

Referenced by lpExactFlushAndSolve(), and SCIPlpiExactSolveBarrier().

◆ SCIPlpiExactSolveBarrier()

SCIP_RETCODE SCIPlpiExactSolveBarrier	(	SCIP_LPIEXACT *	lpi,
		SCIP_Bool	crossover )

calls barrier or interior point algorithm to solve the LP with crossover to simplex basis

Parameters

lpi	LP interface structure
crossover	perform crossover

Definition at line 644 of file lpiexact_none.c.

References assert(), errorMessage(), NULL, SCIP_Bool, SCIP_PLUGINNOTFOUND, SCIPdebugMessage, SCIPlpiExactSolveDual(), and SCIP_LPiExact::spx.

◆ SCIPlpiExactStartStrongbranch()

SCIP_RETCODE SCIPlpiExactStartStrongbranch ( SCIP_LPIEXACT * lpi )

start strong branching - call before any strong branching

start strong branching - call before any strongbranching

Parameters

lpi	LP interface structure

Definition at line 655 of file lpiexact_none.c.

References assert(), errorMessage(), NULL, SPxexSCIP::preStrongbranchingBasisFreed(), SPxexSCIP::savePreStrongbranchingBasis(), SCIP_OKAY, SCIP_PLUGINNOTFOUND, and SCIP_LPiExact::spx.

◆ SCIPlpiExactEndStrongbranch()

SCIP_RETCODE SCIPlpiExactEndStrongbranch ( SCIP_LPIEXACT * lpi )

end strong branching - call after any strong branching

end strong branching - call after any strongbranching

Parameters

lpi	LP interface structure

Definition at line 666 of file lpiexact_none.c.

References assert(), errorMessage(), SPxexSCIP::freePreStrongbranchingBasis(), NULL, SPxexSCIP::preStrongbranchingBasisFreed(), SPxexSCIP::restorePreStrongbranchingBasis(), SCIP_OKAY, SCIP_PLUGINNOTFOUND, and SCIP_LPiExact::spx.

◆ SCIPlpiExactStrongbranch()

SCIP_RETCODE SCIPlpiExactStrongbranch	(	SCIP_LPIEXACT *	lpi,
		int	col,
		const SCIP_RATIONAL *	psol,
		int	itlim,
		SCIP_RATIONAL *	down,
		SCIP_RATIONAL *	up,
		SCIP_Bool *	downvalid,
		SCIP_Bool *	upvalid,
		int *	iter )

performs strong branching iterations on all candidates

Parameters

lpi	LP interface structure
col	column to apply strong branching on
psol	current primal solution value of column
itlim	iteration limit for strong branchings
down	stores dual bound after branching column down
up	stores dual bound after branching column up
downvalid	stores whether the returned down value is a valid dual bound; otherwise, it can only be used as an estimate value
upvalid	stores whether the returned up value is a valid dual bound; otherwise, it can only be used as an estimate value
iter	stores total number of strong branching iterations, or -1; may be NULL

References SCIP_Bool.

◆ SCIPlpiExactWasSolved()

SCIP_Bool SCIPlpiExactWasSolved ( SCIP_LPIEXACT * lpi )

returns whether a solve method was called after the last modification of the LP

Parameters

lpi	LP interface structure

Definition at line 687 of file lpiexact_none.c.

References assert(), errorMessageAbort(), FALSE, NULL, SCIP_Bool, and SCIP_LPiExact::solved.

◆ SCIPlpiExactGetSolFeasibility()

SCIP_RETCODE SCIPlpiExactGetSolFeasibility	(	SCIP_LPIEXACT *	lpi,
		SCIP_Bool *	primalfeasible,
		SCIP_Bool *	dualfeasible )

gets information about primal and dual feasibility of the current LP solution

The feasibility information is with respect to the last solving call and it is only relevant if SCIPlpiWasSolved() returns true. If the LP is changed, this information might be invalidated.

Note that

Parameters

primalfeasible	and
dualfeasible	should only return true if the solver has proved the respective LP to be feasible. Thus, the return values should be equal to the values of SCIPlpiIsPrimalFeasible() and SCIPlpiIsDualFeasible(), respectively. Note that if feasibility cannot be proved, they should return false (even if the problem might actually be feasible).

Parameters

lpi	LP interface structure
primalfeasible	pointer to store primal feasibility status
dualfeasible	pointer to store dual feasibility status

Definition at line 706 of file lpiexact_none.c.

References assert(), errorMessage(), NULL, SCIP_Bool, SCIP_OKAY, SCIP_PLUGINNOTFOUND, SCIPdebugMessage, SCIPlpiExactIsDualFeasible(), and SCIPlpiExactIsPrimalFeasible().

Referenced by lpExactFlushAndSolve().

◆ SCIPlpiExactExistsPrimalRay()

SCIP_Bool SCIPlpiExactExistsPrimalRay ( SCIP_LPIEXACT * lpi )

returns TRUE iff LP is proven to have a primal unbounded ray (but not necessary a primal feasible point); this does not necessarily mean, that the solver knows and can return the primal ray

Parameters

lpi	LP interface structure

Definition at line 722 of file lpiexact_none.c.

References assert(), errorMessageAbort(), FALSE, NULL, SCIP_Bool, SCIPdebugMessage, and SCIP_LPiExact::spx.

Referenced by lpExactFlushAndSolve().

◆ SCIPlpiExactHasPrimalRay()

SCIP_Bool SCIPlpiExactHasPrimalRay ( SCIP_LPIEXACT * lpi )

returns TRUE iff LP is proven to have a primal unbounded ray (but not necessary a primal feasible point), and the solver knows and can return the primal ray

Parameters

lpi	LP interface structure

Definition at line 734 of file lpiexact_none.c.

References assert(), errorMessageAbort(), FALSE, NULL, SCIP_Bool, SCIPdebugMessage, and SCIP_LPiExact::spx.

Referenced by SCIPlpExactGetPrimalRay().

◆ SCIPlpiExactIsPrimalUnbounded()

SCIP_Bool SCIPlpiExactIsPrimalUnbounded ( SCIP_LPIEXACT * lpi )

returns TRUE iff LP is proven to be primal unbounded

Parameters

lpi	LP interface structure

Definition at line 744 of file lpiexact_none.c.

References assert(), errorMessageAbort(), FALSE, NULL, SCIP_Bool, SCIPdebugMessage, and SCIP_LPiExact::spx.

Referenced by lpExactFlushAndSolve().

◆ SCIPlpiExactIsPrimalInfeasible()

SCIP_Bool SCIPlpiExactIsPrimalInfeasible ( SCIP_LPIEXACT * lpi )

returns TRUE iff LP is proven to be primal infeasible

Parameters

lpi	LP interface structure

Definition at line 754 of file lpiexact_none.c.

References assert(), errorMessageAbort(), FALSE, NULL, SCIP_Bool, SCIPdebugMessage, and SCIP_LPiExact::spx.

Referenced by lpExactFlushAndSolve().

◆ SCIPlpiExactIsPrimalFeasible()

SCIP_Bool SCIPlpiExactIsPrimalFeasible ( SCIP_LPIEXACT * lpi )

returns TRUE iff LP is proven to be primal feasible

Parameters

lpi	LP interface structure

Definition at line 764 of file lpiexact_none.c.

References assert(), errorMessageAbort(), FALSE, NULL, SCIP_Bool, SCIPdebugMessage, and SCIP_LPiExact::spx.

Referenced by lpExactFlushAndSolve(), SCIPlpiExactGetSolFeasibility(), and SCIPlpiExactIsOptimal().

◆ SCIPlpiExactExistsDualRay()

SCIP_Bool SCIPlpiExactExistsDualRay ( SCIP_LPIEXACT * lpi )

returns TRUE iff LP is proven to have a dual unbounded ray (but not necessary a dual feasible point); this does not necessarily mean, that the solver knows and can return the dual ray

Parameters

lpi	LP interface structure

Definition at line 776 of file lpiexact_none.c.

References assert(), errorMessageAbort(), FALSE, NULL, SCIP_Bool, SCIPdebugMessage, and SCIP_LPiExact::spx.

◆ SCIPlpiExactHasDualRay()

SCIP_Bool SCIPlpiExactHasDualRay ( SCIP_LPIEXACT * lpi )

returns TRUE iff LP is proven to have a dual unbounded ray (but not necessary a dual feasible point), and the solver knows and can return the dual ray

Parameters

lpi	LP interface structure

Definition at line 788 of file lpiexact_none.c.

References assert(), errorMessageAbort(), FALSE, NULL, SCIP_Bool, SCIPdebugMessage, and SCIP_LPiExact::spx.

Referenced by SCIPlpExactSolveAndEval(), and SCIPlpSolveAndEval().

◆ SCIPlpiExactIsDualUnbounded()

SCIP_Bool SCIPlpiExactIsDualUnbounded ( SCIP_LPIEXACT * lpi )

returns TRUE iff LP is proven to be dual unbounded

returns TRUE iff LP is dual unbounded

Parameters

lpi	LP interface structure

Definition at line 798 of file lpiexact_none.c.

References assert(), errorMessageAbort(), FALSE, NULL, SCIP_Bool, SCIPdebugMessage, and SCIP_LPiExact::spx.

◆ SCIPlpiExactIsDualInfeasible()

SCIP_Bool SCIPlpiExactIsDualInfeasible ( SCIP_LPIEXACT * lpi )

returns TRUE iff LP is proven to be dual infeasible

returns TRUE iff LP is dual infeasible

Parameters

lpi	LP interface structure

Definition at line 808 of file lpiexact_none.c.

References assert(), errorMessageAbort(), FALSE, NULL, SCIP_Bool, SCIPdebugMessage, and SCIP_LPiExact::spx.

◆ SCIPlpiExactIsDualFeasible()

SCIP_Bool SCIPlpiExactIsDualFeasible ( SCIP_LPIEXACT * lpi )

returns TRUE iff LP is proven to be dual feasible

Parameters

lpi	LP interface structure

Definition at line 818 of file lpiexact_none.c.

References assert(), errorMessageAbort(), FALSE, NULL, SCIP_Bool, SCIPdebugMessage, and SCIP_LPiExact::spx.

Referenced by lpExactFlushAndSolve(), SCIPlpiExactGetSolFeasibility(), and SCIPlpiExactIsOptimal().

◆ SCIPlpiExactIsOptimal()

SCIP_Bool SCIPlpiExactIsOptimal ( SCIP_LPIEXACT * lpi )

returns TRUE iff LP was solved to optimality

Parameters

lpi	LP interface structure

Definition at line 828 of file lpiexact_none.c.

References assert(), errorMessageAbort(), FALSE, NULL, SCIP_Bool, SCIPdebugMessage, SCIPlpiExactIsDualFeasible(), SCIPlpiExactIsPrimalFeasible(), and SCIP_LPiExact::spx.

Referenced by lpExactFlushAndSolve().

◆ SCIPlpiExactIsStable()

SCIP_Bool SCIPlpiExactIsStable ( SCIP_LPIEXACT * lpi )

returns TRUE iff current LP solution is stable

This function should return true if the solution is reliable, i.e., feasible and optimal (or proven infeasible/unbounded) with respect to the original problem. The optimality status might be with respect to a scaled version of the problem, but the solution might not be feasible to the unscaled original problem; in this case, SCIPlpiIsStable() should return false.

Parameters

lpi	LP interface structure

References c, objval, primsol, r, and SCIP_Bool.

◆ SCIPlpiExactIsObjlimExc()

SCIP_Bool SCIPlpiExactIsObjlimExc ( SCIP_LPIEXACT * lpi )

returns TRUE iff the objective limit was reached

Parameters

lpi	LP interface structure

Definition at line 838 of file lpiexact_none.c.

References assert(), errorMessageAbort(), FALSE, NULL, SCIP_Bool, SCIPdebugMessage, and SCIP_LPiExact::spx.

Referenced by lpExactFlushAndSolve().

◆ SCIPlpiExactIsIterlimExc()

SCIP_Bool SCIPlpiExactIsIterlimExc ( SCIP_LPIEXACT * lpi )

returns TRUE iff the iteration limit was reached

Parameters

lpi	LP interface structure

Definition at line 848 of file lpiexact_none.c.

References assert(), errorMessageAbort(), FALSE, NULL, SCIP_Bool, SCIPdebugMessage, and SCIP_LPiExact::spx.

Referenced by lpExactFlushAndSolve().

◆ SCIPlpiExactIsTimelimExc()

SCIP_Bool SCIPlpiExactIsTimelimExc ( SCIP_LPIEXACT * lpi )

returns TRUE iff the time limit was reached

Parameters

lpi	LP interface structure

Definition at line 858 of file lpiexact_none.c.

References assert(), errorMessageAbort(), FALSE, NULL, SCIP_Bool, SCIPdebugMessage, and SCIP_LPiExact::spx.

Referenced by lpExactFlushAndSolve().

◆ SCIPlpiExactGetInternalStatus()

int SCIPlpiExactGetInternalStatus ( SCIP_LPIEXACT * lpi )

returns the internal solution status of the solver

Parameters

lpi	LP interface structure

Definition at line 868 of file lpiexact_none.c.

References assert(), errorMessageAbort(), FALSE, NULL, SCIPdebugMessage, and SCIP_LPiExact::spx.

Referenced by lpExactFlushAndSolve().

◆ SCIPlpiExactIgnoreInstability()

SCIP_RETCODE SCIPlpiExactIgnoreInstability	(	SCIP_LPIEXACT *	lpi,
		SCIP_Bool *	success )

tries to reset the internal status of the LP solver in order to ignore an instability of the last solving call

Parameters

lpi	LP interface structure
success	pointer to store, whether the instability could be ignored

Definition at line 878 of file lpiexact_none.c.

References assert(), errorMessage(), FALSE, NULL, SCIP_Bool, SCIP_OKAY, SCIP_PLUGINNOTFOUND, SCIPdebugMessage, and SCIP_LPiExact::spx.

◆ SCIPlpiExactGetObjval()

SCIP_RETCODE SCIPlpiExactGetObjval	(	SCIP_LPIEXACT *	lpi,
		SCIP_RATIONAL *	objval )

gets objective value of solution

Parameters

lpi	LP interface structure
objval	stores the objective value

Definition at line 890 of file lpiexact_none.c.

References assert(), errorMessage(), NULL, objval, RsetSpxR(), SCIP_OKAY, SCIP_PLUGINNOTFOUND, SCIPdebugMessage, and SCIP_LPiExact::spx.

Referenced by lpExactFlushAndSolve(), SCIPcertificatePrintDualboundExactLP(), and SCIPlpExactSolveAndEval().

◆ SCIPlpiExactGetSol()

SCIP_RETCODE SCIPlpiExactGetSol	(	SCIP_LPIEXACT *	lpi,
		SCIP_RATIONAL *	objval,
		SCIP_RATIONAL **	primsol,
		SCIP_RATIONAL **	dualsol,
		SCIP_RATIONAL **	activity,
		SCIP_RATIONAL **	redcost )

gets primal and dual solution vectors for feasible LPs

Before calling this function, the caller must ensure that the LP has been solved to optimality, i.e., that SCIPlpiIsOptimal() returns true.

Parameters

lpi	LP interface structure
objval	stores the objective value, may be NULL if not needed
primsol	primal solution vector, may be NULL if not needed
dualsol	dual solution vector, may be NULL if not needed
activity	row activity vector, may be NULL if not needed
redcost	reduced cost vector, may be NULL if not needed

Definition at line 907 of file lpiexact_none.c.

References assert(), errorMessage(), MAX, SCIP_LPiExact::messagehdlr, NULL, objval, primsol, RsetSpxR(), RsetSpxVector(), SCIP_LPERROR, SCIP_OKAY, SCIP_PLUGINNOTFOUND, SCIPdebugMessage, SCIPmessagePrintWarning(), SCIP_LPiExact::spx, and x.

Referenced by SCIPlpExactGetSol().

◆ SCIPlpiExactGetPrimalRay()

SCIP_RETCODE SCIPlpiExactGetPrimalRay	(	SCIP_LPIEXACT *	lpi,
		SCIP_RATIONAL **	ray )

gets primal ray for unbounded LPs

Parameters

lpi	LP interface structure
ray	primal ray

Definition at line 923 of file lpiexact_none.c.

References assert(), errorMessage(), MAX, SCIP_LPiExact::messagehdlr, NULL, RsetSpxVector(), SCIP_LPERROR, SCIP_OKAY, SCIP_PLUGINNOTFOUND, SCIPdebugMessage, SCIPmessagePrintWarning(), SCIP_LPiExact::spx, and x.

Referenced by SCIPlpExactGetPrimalRay().

◆ SCIPlpiExactGetDualfarkas()

SCIP_RETCODE SCIPlpiExactGetDualfarkas	(	SCIP_LPIEXACT *	lpi,
		SCIP_RATIONAL **	dualfarkas )

gets dual farkas proof for infeasibility

Parameters

lpi	LP interface structure
dualfarkas	dual farkas row multipliers

Definition at line 934 of file lpiexact_none.c.

References assert(), errorMessage(), MAX, SCIP_LPiExact::messagehdlr, NULL, RsetSpxVector(), SCIP_LPERROR, SCIP_OKAY, SCIP_PLUGINNOTFOUND, SCIPdebugMessage, SCIPmessagePrintWarning(), SCIP_LPiExact::spx, and x.

Referenced by SCIPlpExactGetDualfarkas().

◆ SCIPlpiExactGetIterations()

SCIP_RETCODE SCIPlpiExactGetIterations	(	SCIP_LPIEXACT *	lpi,
		int *	iterations )

gets the number of LP iterations of the last solve call

Parameters

lpi	LP interface structure
iterations	pointer to store the number of iterations of the last solve call

Definition at line 945 of file lpiexact_none.c.

References assert(), errorMessage(), NULL, SCIP_OKAY, SCIP_PLUGINNOTFOUND, SCIPdebugMessage, and SCIP_LPiExact::spx.

Referenced by SCIPlpExactGetIterations().

◆ SCIPlpiExactGetBase()

SCIP_RETCODE SCIPlpiExactGetBase	(	SCIP_LPIEXACT *	lpi,
		int *	cstat,
		int *	rstat )

gets current basis status for columns and rows; arrays must be large enough to store the basis status

Parameters

lpi	LP interface structure
cstat	array to store column basis status, or NULL
rstat	array to store row basis status, or NULL

Definition at line 967 of file lpiexact_none.c.

References assert(), errorMessage(), i, NULL, SPxexSCIP::preStrongbranchingBasisFreed(), SCIP_BASESTAT_BASIC, SCIP_BASESTAT_LOWER, SCIP_BASESTAT_UPPER, SCIP_BASESTAT_ZERO, SCIP_INVALIDDATA, SCIP_LPERROR, SCIP_OKAY, SCIP_PLUGINNOTFOUND, SCIPABORT, SCIPdebugMessage, SCIPerrorMessage, and SCIP_LPiExact::spx.

Referenced by SCIPlpExactGetSol(), and SCIPlpiExactGetState().

◆ SCIPlpiExactSetBase()

SCIP_RETCODE SCIPlpiExactSetBase	(	SCIP_LPIEXACT *	lpi,
		int *	cstat,
		int *	rstat )

sets current basis status for columns and rows

Parameters

lpi	LP interface structure
cstat	array with column basis status
rstat	array with row basis status

Definition at line 979 of file lpiexact_none.c.

References assert(), SPxexSCIP::colStat(), errorMessage(), SPxexSCIP::freePreStrongbranchingBasis(), i, invalidateSolution(), SCIP_LPiExact::messagehdlr, NULL, SPxexSCIP::preStrongbranchingBasisFreed(), SPxexSCIP::rowStat(), SCIP_BASESTAT_BASIC, SCIP_BASESTAT_LOWER, SCIP_BASESTAT_UPPER, SCIP_BASESTAT_ZERO, SCIP_CALL, SCIP_INVALIDDATA, SCIP_LPERROR, SCIP_OKAY, SCIP_PLUGINNOTFOUND, SCIPABORT, SCIPdebugMessage, SCIPerrorMessage, SCIPlpiExactGetNCols(), SCIPlpiExactGetNRows(), SOPLEX_TRY, and SCIP_LPiExact::spx.

Referenced by lpExactFlushAndSolve(), and SCIPlpiExactSetState().

◆ SCIPlpiExactGetBasisInd()

SCIP_RETCODE SCIPlpiExactGetBasisInd	(	SCIP_LPIEXACT *	lpi,
		int *	bind )

returns the indices of the basic columns and rows

returns the indices of the basic columns and rows; basic column n gives value n, basic row m gives value -1-m

Parameters

lpi	LP interface structure
bind	pointer to store basis indices ready to keep number of rows entries

Definition at line 993 of file lpiexact_none.c.

References assert(), errorMessage(), NULL, SPxexSCIP::preStrongbranchingBasisFreed(), SCIP_OKAY, SCIP_PLUGINNOTFOUND, SCIPdebugMessage, and SCIP_LPiExact::spx.

◆ SCIPlpiExactGetBInvRow()

SCIP_RETCODE SCIPlpiExactGetBInvRow	(	SCIP_LPIEXACT *	lpi,
		int	r,
		SCIP_RATIONAL **	coef,
		int *	inds,
		int *	ninds )

get dense row of inverse basis matrix B^-1

get row of inverse basis matrix B^-1

Note: The LP interface defines slack variables to have coefficient +1. This means that if, internally, the LP solver uses a -1 coefficient, then rows associated with slacks variables whose coefficient is -1, should be negated; see also the explanation in lpi.h.

Parameters

lpi	LP interface structure
r	row number
coef	pointer to store the coefficients of the row
inds	array to store the non-zero indices, or NULL
ninds	pointer to store the number of non-zero indices, or NULL (-1: if we do not store sparsity information)

Definition at line 1010 of file lpiexact_none.c.

References assert(), errorMessage(), i, NULL, SPxexSCIP::preStrongbranchingBasisFreed(), r, RsetSpxR(), SCIP_LPERROR, SCIP_OKAY, SCIP_PLUGINNOTFOUND, SCIPdebugMessage, and SCIP_LPiExact::spx.

◆ SCIPlpiExactGetBInvCol()

SCIP_RETCODE SCIPlpiExactGetBInvCol	(	SCIP_LPIEXACT *	lpi,
		int	c,
		SCIP_RATIONAL **	coef,
		int *	inds,
		int *	ninds )

get dense column of inverse basis matrix B^-1

get column of inverse basis matrix B^-1

Note: The LP interface defines slack variables to have coefficient +1. This means that if, internally, the LP solver uses a -1 coefficient, then rows associated with slacks variables whose coefficient is -1, should be negated; see also the explanation in lpi.h.

Parameters

lpi	LP interface structure
c	column number of B^-1; this is NOT the number of the column in the LP; you have to call SCIPlpiExactGetBasisInd() to get the array which links the B^-1 column numbers to the row and column numbers of the LP! c must be between 0 and nrows-1, since the basis has the size nrows * nrows
coef	pointer to store the coefficients of the column
inds	array to store the non-zero indices, or NULL
ninds	pointer to store the number of non-zero indices, or NULL (-1: if we do not store sparsity information)

Definition at line 1031 of file lpiexact_none.c.

References assert(), c, errorMessage(), i, NULL, SPxexSCIP::preStrongbranchingBasisFreed(), RsetSpxR(), SCIP_LPERROR, SCIP_OKAY, SCIP_PLUGINNOTFOUND, SCIPdebugMessage, and SCIP_LPiExact::spx.

◆ SCIPlpiExactGetBInvARow()

SCIP_RETCODE SCIPlpiExactGetBInvARow	(	SCIP_LPIEXACT *	lpi,
		int	r,
		SCIP_RATIONAL **	binvrow,
		SCIP_RATIONAL **	coef,
		int *	inds,
		int *	ninds )

get dense row of inverse basis matrix times constraint matrix B^-1 * A

Parameters

lpi	LP interface structure
r	row number
binvrow	row in (A_B)^-1 from prior call to SCIPlpiExactGetBInvRow(), or NULL
coef	vector to return coefficients
inds	array to store the non-zero indices, or NULL
ninds	pointer to store the number of non-zero indices, or NULL (-1: if we do not store sparsity information)

References r.

◆ SCIPlpiExactGetBInvACol()

SCIP_RETCODE SCIPlpiExactGetBInvACol	(	SCIP_LPIEXACT *	lpi,
		int	c,
		SCIP_RATIONAL **	coef,
		int *	inds,
		int *	ninds )

get dense column of inverse basis matrix times constraint matrix B^-1 * A

Parameters

lpi	LP interface structure
c	column number
coef	vector to return coefficients
inds	array to store the non-zero indices, or NULL
ninds	pointer to store the number of non-zero indices, or NULL (-1: if we do not store sparsity information)

References c, and SCIP_Bool.

◆ SCIPlpiExactGetState()

SCIP_RETCODE SCIPlpiExactGetState	(	SCIP_LPIEXACT *	lpi,
		BMS_BLKMEM *	blkmem,
		SCIP_LPISTATE **	lpistate )

stores LPi state (like basis information) into lpistate object

Parameters

lpi	LP interface structure
blkmem	block memory
lpistate	pointer to LPi state information (like basis information)

Definition at line 1061 of file lpiexact_none.c.

References assert(), SCIP_LPiExact::cstat, ensureCstatMem(), ensureRstatMem(), errorMessage(), lpistateCreate(), lpistatePack(), NULL, SPxexSCIP::preStrongbranchingBasisFreed(), SCIP_LPiExact::rstat, SCIP_CALL, SCIP_OKAY, SCIP_PLUGINNOTFOUND, SCIPdebugMessage, SCIPlpiExactGetBase(), and SCIP_LPiExact::spx.

Referenced by SCIPlpExactGetState(), and SCIPlpExactStartDive().

◆ SCIPlpiExactSetState()

SCIP_RETCODE SCIPlpiExactSetState	(	SCIP_LPIEXACT *	lpi,
		BMS_BLKMEM *	blkmem,
		SCIP_LPISTATE *	lpistate )

loads LPi state (like basis information) into solver; note that the LP might have been extended with additional columns and rows since the state was stored with SCIPlpiExactGetState()

Parameters

lpi	LP interface structure
blkmem	block memory
lpistate	LPi state information (like basis information), or NULL

Definition at line 1078 of file lpiexact_none.c.

References assert(), SCIP_LPiExact::cstat, ensureCstatMem(), ensureRstatMem(), errorMessage(), i, lpistateUnpack(), SCIP_LPiState::ncols, SCIP_LPiState::nrows, NULL, SPxexSCIP::preStrongbranchingBasisFreed(), REALABS, SCIP_LPiExact::rstat, SCIP_BASESTAT_BASIC, SCIP_BASESTAT_LOWER, SCIP_BASESTAT_UPPER, SCIP_BASESTAT_ZERO, SCIP_CALL, SCIP_OKAY, SCIP_PLUGINNOTFOUND, SCIP_Real, SCIPdebugMessage, SCIPlpiExactIsInfinity(), SCIPlpiExactSetBase(), and SCIP_LPiExact::spx.

Referenced by SCIPlpExactSetState().

◆ SCIPlpiExactClearState()

SCIP_RETCODE SCIPlpiExactClearState ( SCIP_LPIEXACT * lpi )

clears current LPi state (like basis information) of the solver

Parameters

lpi	LP interface structure

Definition at line 1092 of file lpiexact_none.c.

References assert(), SCIP_LPiExact::messagehdlr, NULL, SCIP_LPERROR, SCIP_OKAY, SCIPdebugMessage, SCIPmessagePrintWarning(), SCIP_LPiExact::spx, and x.

◆ SCIPlpiExactFreeState()

SCIP_RETCODE SCIPlpiExactFreeState	(	SCIP_LPIEXACT *	lpi,
		BMS_BLKMEM *	blkmem,
		SCIP_LPISTATE **	lpistate )

frees LPi state information

Parameters

lpi	LP interface structure
blkmem	block memory
lpistate	pointer to LPi state information (like basis information)

Definition at line 1101 of file lpiexact_none.c.

References assert(), lpistateFree(), NULL, SCIP_OKAY, and SCIPdebugMessage.

Referenced by SCIPlpExactFreeState().

◆ SCIPlpiExactHasStateBasis()

SCIP_Bool SCIPlpiExactHasStateBasis	(	SCIP_LPIEXACT *	lpi,
		SCIP_LPISTATE *	lpistate )

checks, whether the given LPi state contains simplex basis information

checks, whether the given LP state contains simplex basis information

Parameters

lpi	LP interface structure
lpistate	LP state information (like basis information), or NULL

Definition at line 1114 of file lpiexact_none.c.

References assert(), errorMessageAbort(), FALSE, NULL, SCIP_Bool, and TRUE.

Referenced by SCIPlpExactSetState().

◆ SCIPlpiExactReadState()

SCIP_RETCODE SCIPlpiExactReadState	(	SCIP_LPIEXACT *	lpi,
		const char *	fname )

reads LPi state (like basis information from a file

reads LP state (like basis information from a file

Parameters

lpi	LP interface structure
fname	file name

Definition at line 1125 of file lpiexact_none.c.

References assert(), errorMessage(), SCIP_LPiExact::messagehdlr, NULL, SPxexSCIP::preStrongbranchingBasisFreed(), SCIP_LPERROR, SCIP_OKAY, SCIP_PLUGINNOTFOUND, SCIPdebugMessage, SOPLEX_TRY, and SCIP_LPiExact::spx.

◆ SCIPlpiExactWriteState()

SCIP_RETCODE SCIPlpiExactWriteState	(	SCIP_LPIEXACT *	lpi,
		const char *	fname )

writes LPi state (like basis information) to a file

writes LPi state (i.e. basis information) to a file

Parameters

lpi	LP interface structure
fname	file name

Definition at line 1137 of file lpiexact_none.c.

References assert(), errorMessage(), SCIP_LPiExact::messagehdlr, NULL, SPxexSCIP::preStrongbranchingBasisFreed(), SCIP_LPERROR, SCIP_OKAY, SCIP_PLUGINNOTFOUND, SCIPdebugMessage, SOPLEX_TRY, and SCIP_LPiExact::spx.

◆ SCIPlpiExactStateDualFeasible()

SCIP_RETCODE SCIPlpiExactStateDualFeasible	(	SCIP_LPIEXACT *	lpi,
		BMS_BLKMEM *	blkmem,
		SCIP_LPISTATE *	lpistate,
		SCIP_Bool	useprestep,
		SCIP_Real *	primalsol,
		SCIP_Real *	dualsol,
		SCIP_Bool *	result,
		SCIP_RATIONAL **	dualobjval )

checks whether LPi state (i.e. basis information) is dual feasbile and returns corresponding dual objective value. if wanted it will first directly test the corresponding approximate dual and primal solution (corrected via dual variables for bounds and primal variables for slacks if possible) for optimality before performing the dual feasibility test on the more expensive exact basic solution.

Parameters

lpi	LP interface structure
blkmem	block memory
lpistate	LPi state information (like basis information)
useprestep	should approximate primal and dual solution first
primalsol	approximate primal solution; or NULL to compute by exact LP solver
dualsol	approximate dual solution; or NULL to compute by exact LP solver
result	pointer to store whether given LPi state is dual feasible
dualobjval	pointer to store dual objective value in case of dual feasibility

References result, SCIP_Bool, and SCIP_Real.

◆ SCIPlpiExactGetNorms()

SCIP_RETCODE SCIPlpiExactGetNorms	(	SCIP_LPIEXACT *	lpi,
		BMS_BLKMEM *	blkmem,
		SCIP_LPINORMS **	lpinorms )

stores lpiexact pricing norms into lpiexactnorms object

Parameters

lpi	LP interface structure
blkmem	block memory
lpinorms	pointer to LPi pricing norms information

◆ SCIPlpiExactSetNorms()

SCIP_RETCODE SCIPlpiExactSetNorms	(	SCIP_LPIEXACT *	lpi,
		BMS_BLKMEM *	blkmem,
		const SCIP_LPINORMS *	lpinorms )

loads LPi pricing norms into solver; note that the LP might have been extended with additional columns and rows since the norms were stored with SCIPlpiGetNorms()

Parameters

lpi	LP interface structure
blkmem	block memory
lpinorms	LPi pricing norms information, or NULL

◆ SCIPlpiExactFreeNorms()

SCIP_RETCODE SCIPlpiExactFreeNorms	(	SCIP_LPIEXACT *	lpi,
		BMS_BLKMEM *	blkmem,
		SCIP_LPINORMS **	lpinorms )

frees LPi pricing norms information

Parameters

lpi	LP interface structure
blkmem	block memory
lpinorms	pointer to LPi pricing norms information, or NULL

References SCIP_Real.

◆ SCIPlpiExactGetIntpar()

SCIP_RETCODE SCIPlpiExactGetIntpar	(	SCIP_LPIEXACT *	lpi,
		SCIP_LPPARAM	type,
		int *	ival )

gets integer parameter of LP

Parameters

lpi	LP interface structure
type	parameter number
ival	buffer to store the parameter value

Definition at line 1159 of file lpiexact_none.c.

References assert(), SPxexSCIP::getFromScratch(), SPxexSCIP::getLpInfo(), NULL, SCIP_LPiExact::pricing, SCIP_LPPAR_FROMSCRATCH, SCIP_LPPAR_LPINFO, SCIP_LPPAR_LPITLIM, SCIP_LPPAR_PRESOLVING, SCIP_LPPAR_PRICING, SCIP_LPPAR_RANDOMSEED, SCIP_LPPAR_REFACTOR, SCIP_LPPAR_SCALING, SCIP_LPPAR_TIMING, SCIP_OKAY, SCIP_PARAMETERUNKNOWN, SCIPdebugMessage, and SCIP_LPiExact::spx.

Referenced by SCIPlpExactStartDive().

◆ SCIPlpiExactSetIntpar()

SCIP_RETCODE SCIPlpiExactSetIntpar	(	SCIP_LPIEXACT *	lpi,
		SCIP_LPPARAM	type,
		int	ival )

sets integer parameter of LP

Parameters

lpi	LP interface structure
type	parameter number
ival	parameter value

Definition at line 1171 of file lpiexact_none.c.

References assert(), FALSE, NULL, SCIP_LPiExact::pricing, SCIP_LPERROR, SCIP_LPPAR_FROMSCRATCH, SCIP_LPPAR_LPINFO, SCIP_LPPAR_LPITLIM, SCIP_LPPAR_POLISHING, SCIP_LPPAR_PRESOLVING, SCIP_LPPAR_PRICING, SCIP_LPPAR_RANDOMSEED, SCIP_LPPAR_REFACTOR, SCIP_LPPAR_SCALING, SCIP_LPPAR_TIMING, SCIP_OKAY, SCIP_PARAMETERUNKNOWN, SCIP_PRICING_AUTO, SCIP_PRICING_DEVEX, SCIP_PRICING_FULL, SCIP_PRICING_LPIDEFAULT, SCIP_PRICING_PARTIAL, SCIP_PRICING_STEEP, SCIP_PRICING_STEEPQSTART, SCIPdebugMessage, SPxexSCIP::setFromScratch(), SPxexSCIP::setLpInfo(), SCIP_LPiExact::spx, and TRUE.

Referenced by lpExactFlushAndSolve(), lpExactSetIntpar(), and SCIPlpiExactCreate().

◆ SCIPlpiExactGetRealpar()

SCIP_RETCODE SCIPlpiExactGetRealpar	(	SCIP_LPIEXACT *	lpi,
		SCIP_LPPARAM	type,
		SCIP_Real *	dval )

gets floating point parameter of LP

Parameters

lpi	LP interface structure
type	parameter number
dval	buffer to store the parameter value

Definition at line 1182 of file lpiexact_none.c.

References assert(), SCIP_LPiExact::conditionlimit, NULL, SCIP_LPPAR_CONDITIONLIMIT, SCIP_LPPAR_DUALFEASTOL, SCIP_LPPAR_FEASTOL, SCIP_LPPAR_LPTILIM, SCIP_LPPAR_OBJLIM, SCIP_LPPAR_ROWREPSWITCH, SCIP_OKAY, SCIP_PARAMETERUNKNOWN, SCIP_Real, SCIPdebugMessage, SCIPlpiExactInfinity(), and SCIP_LPiExact::spx.

Referenced by lpExactSetObjlim().

◆ SCIPlpiExactSetRealpar()

SCIP_RETCODE SCIPlpiExactSetRealpar	(	SCIP_LPIEXACT *	lpi,
		SCIP_LPPARAM	type,
		SCIP_Real	dval )

sets floating point parameter of LP

Parameters

lpi	LP interface structure
type	parameter number
dval	parameter value

Definition at line 1194 of file lpiexact_none.c.

References assert(), SCIP_LPiExact::checkcondition, SCIP_LPiExact::conditionlimit, NULL, SCIP_LPPAR_CONDITIONLIMIT, SCIP_LPPAR_LPTILIM, SCIP_LPPAR_OBJLIM, SCIP_LPPAR_ROWREPSWITCH, SCIP_OKAY, SCIP_PARAMETERUNKNOWN, SCIP_Real, SCIPdebugMessage, SCIPlpiExactInfinity(), and SCIP_LPiExact::spx.

Referenced by lpExactSetRealpar().

◆ SCIPlpiExactPosInfinity()

void SCIPlpiExactPosInfinity	(	SCIP_LPIEXACT *	lpi,
		SCIP_RATIONAL *	infval )

returns value treated as positive infinity in the LP solver

Parameters

lpi	LP interface structure
infval	pointer to store positive infinity value of LP solver

◆ SCIPlpiExactIsPosInfinity()

SCIP_Bool SCIPlpiExactIsPosInfinity	(	SCIP_LPIEXACT *	lpi,
		SCIP_RATIONAL *	val )

checks if given value is treated as positive infinity in the LP solver

Parameters

lpi	LP interface structure
val	given value

References SCIP_Bool.

◆ SCIPlpiExactNegInfinity()

void SCIPlpiExactNegInfinity	(	SCIP_LPIEXACT *	lpi,
		SCIP_RATIONAL *	infval )

returns value treated as negative infinity in the LP solver

Parameters

lpi	LP interface structure
infval	pointer to store negative infinity value of LP solver

◆ SCIPlpiExactIsNegInfinity()

SCIP_Bool SCIPlpiExactIsNegInfinity	(	SCIP_LPIEXACT *	lpi,
		SCIP_RATIONAL *	val )

checks if given value is treated as negative infinity in the LP solver

Parameters

lpi	LP interface structure
val	given value

References SCIP_Bool, and SCIP_Real.

◆ SCIPlpiExactInfinity()

SCIP_Real SCIPlpiExactInfinity ( SCIP_LPIEXACT * lpi )

returns value treated as infinity in the LP solver

Parameters

lpi	LP interface structure

Definition at line 1216 of file lpiexact_none.c.

References assert(), LPIINFINITY, NULL, SCIP_Real, SCIPdebugMessage, and SCIP_LPiExact::spx.

Referenced by lpExactFlushAndSolve(), lpExactSetObjlim(), SCIPlpExactCreate(), SCIPlpiExactGetRealpar(), SCIPlpiExactSetRealpar(), and SpxRSetRat().

◆ SCIPlpiExactIsInfinity()

SCIP_Bool SCIPlpiExactIsInfinity	(	SCIP_LPIEXACT *	lpi,
		SCIP_Real	val )

checks if given value is treated as infinity in the LP solver

Parameters

lpi	LP interface structure
val	the value

Definition at line 1225 of file lpiexact_none.c.

References assert(), FALSE, LPIINFINITY, NULL, SCIP_Bool, SCIP_Real, SCIPdebugMessage, SCIP_LPiExact::spx, and TRUE.

Referenced by RsetSpxR(), and SCIPlpiExactSetState().

◆ SCIPlpiExactReadLP()

SCIP_RETCODE SCIPlpiExactReadLP	(	SCIP_LPIEXACT *	lpi,
		const char *	fname )

reads LP from a file

Parameters

lpi	LP interface structure
fname	file name

Definition at line 1247 of file lpiexact_none.c.

References assert(), errorMessage(), fileExists(), SCIP_LPiExact::messagehdlr, NULL, SPxexSCIP::preStrongbranchingBasisFreed(), SCIP_NOFILE, SCIP_OKAY, SCIP_PLUGINNOTFOUND, SCIP_READERROR, SCIPdebugMessage, SCIPmessagePrintWarning(), SCIP_LPiExact::spx, and x.

◆ SCIPlpiExactWriteLP()

SCIP_RETCODE SCIPlpiExactWriteLP	(	SCIP_LPIEXACT *	lpi,
		const char *	fname )

writes LP to a file

Parameters

lpi	LP interface structure
fname	file name

Definition at line 1259 of file lpiexact_none.c.

References assert(), errorMessage(), SCIP_LPiExact::messagehdlr, NULL, SCIP_OKAY, SCIP_PLUGINNOTFOUND, SCIP_WRITEERROR, SCIPdebugMessage, SCIPmessagePrintWarning(), SCIP_LPiExact::spx, and x.

Referenced by SCIPlpExactWrite().

◆ SCIPlpiExactCreateFactor()

SCIP_RETCODE SCIPlpiExactCreateFactor	(	SCIP_LPIEXACT *	lpi,
		int	dim,
		int *	cbeg,
		int *	clen,
		int *	cindx,
		SCIP_RATIONAL *	ccoef )

computes and stores matrix factorization within the LPIEXACT structure

Parameters

lpi	LP interface structure
dim	dimension of matrix
cbeg	column indices of matrix
clen	column lengths of matrix
cindx	row index of entries
ccoef	coef values of matrix

◆ SCIPlpiExactFactorSolve()

SCIP_RETCODE SCIPlpiExactFactorSolve	(	SCIP_LPIEXACT *	lpi,
		int	dim,
		SCIP_RATIONAL *	sol,
		SCIP_RATIONAL *	rhs )

solves a system using the stored factorization

Parameters

lpi	LP interface structure
dim	dimension of matrix
sol	solution to system
rhs	rhs of system

References sol.

◆ SCIPlpiExactSetIntegralityInformation()

SCIP_RETCODE SCIPlpiExactSetIntegralityInformation	(	SCIP_LPIEXACT *	lpi,
		int	ncols,
		int *	intInfo )

pass integrality information about variables to the solver

Parameters

lpi	pointer to an LP interface structure
ncols	length of integrality array
intInfo	integrality array (0: continuous, 1: integer). May be NULL iff ncols is 0.

Definition at line 794 of file lpiexact_spx.cpp.

References assert(), NULL, SCIP_OKAY, and SCIP_LPiExact::spx.

◆ SCIPlpiExactHasPrimalSolve()

SCIP_Bool SCIPlpiExactHasPrimalSolve ( void )

informs about availability of a primal simplex solving method

Definition at line 806 of file lpiexact_spx.cpp.

References SCIP_Bool, and TRUE.

◆ SCIPlpiExactHasDualSolve()

SCIP_Bool SCIPlpiExactHasDualSolve ( void )

informs about availability of a dual simplex solving method

Definition at line 814 of file lpiexact_spx.cpp.

References SCIP_Bool, and TRUE.

◆ SCIPlpiExactHasBarrierSolve()

SCIP_Bool SCIPlpiExactHasBarrierSolve ( void )

informs about availability of a barrier solving method

Definition at line 822 of file lpiexact_spx.cpp.

References FALSE, and SCIP_Bool.

◆ SCIPlpiDelColset()

SCIP_RETCODE SCIPlpiDelColset	(	SCIP_LPIEXACT *	lpi,
		int *	dstat )

deletes columns from SCIP_LP; the new position of a column must not be greater that its old position

Parameters

lpi	LP interface structure
dstat	deletion status of columns input: 1 if column should be deleted, 0 if not output: new position of column, -1 if column was deleted

Definition at line 1132 of file lpiexact_spx.cpp.

References assert(), i, invalidateSolution(), SCIP_LPiExact::messagehdlr, NULL, SPxexSCIP::preStrongbranchingBasisFreed(), SCIP_OKAY, SCIPdebugMessage, SOPLEX_TRY, and SCIP_LPiExact::spx.

Detailed Description

Files

Miscellaneous Methods

LPI Creation and Destruction Methods

Modification Methods

Data Accessing Methods

Solving Methods

Solution Information Methods

LP Basis Methods

LPi State Methods

LPi Pricing Norms Methods

Parameter Methods

Numerical Methods

File Interface Methods

Exact LU decomposition solver interface

Miscellaneous Methods

Modification Methods

Function Documentation

◆ SCIPlpiExactGetSolverName()

◆ SCIPlpiExactGetSolverDesc()

◆ SCIPlpiExactGetExternalCodeName()

◆ SCIPlpiExactPrintInfo()

◆ SCIPlpiExactGetExternalCodeDesc()

◆ SCIPlpiExactGetSolverPointer()

◆ SCIPlpiExactStart()

◆ SCIPlpiExactEnd()

◆ SCIPlpiExactCreate()

◆ SCIPlpiExactFree()

◆ SCIPlpiExactLoadColLP()

◆ SCIPlpiExactAddCols()

◆ SCIPlpiExactDelCols()

◆ SCIPlpiExactDelColset()

◆ SCIPlpiExactAddRows()

◆ SCIPlpiExactDelRows()

◆ SCIPlpiExactDelRowset()

◆ SCIPlpiExactClear()

◆ SCIPlpiExactChgBounds()

◆ SCIPlpiExactChgSides()

◆ SCIPlpiExactChgCoef()

◆ SCIPlpiExactChgObjsen()

◆ SCIPlpiExactChgObj()

◆ SCIPlpiExactScaleRow()

◆ SCIPlpiExactScaleCol()

◆ SCIPlpiExactGetNRows()

◆ SCIPlpiExactGetNCols()

◆ SCIPlpiExactGetObjsen()

◆ SCIPlpiExactGetNNonz()

◆ SCIPlpiExactGetCols()

◆ SCIPlpiExactGetRows()

◆ SCIPlpiExactGetColNames()

◆ SCIPlpiExactGetRowNames()

◆ SCIPlpiExactGetObj()

◆ SCIPlpiExactGetBounds()

◆ SCIPlpiExactGetSides()

◆ SCIPlpiExactGetCoef()

◆ SCIPlpiExactSolvePrimal()

◆ SCIPlpiExactSolveDual()

◆ SCIPlpiExactSolveBarrier()

◆ SCIPlpiExactStartStrongbranch()

◆ SCIPlpiExactEndStrongbranch()

◆ SCIPlpiExactStrongbranch()

◆ SCIPlpiExactWasSolved()

◆ SCIPlpiExactGetSolFeasibility()

◆ SCIPlpiExactExistsPrimalRay()

◆ SCIPlpiExactHasPrimalRay()

◆ SCIPlpiExactIsPrimalUnbounded()

◆ SCIPlpiExactIsPrimalInfeasible()

◆ SCIPlpiExactIsPrimalFeasible()

◆ SCIPlpiExactExistsDualRay()

◆ SCIPlpiExactHasDualRay()

◆ SCIPlpiExactIsDualUnbounded()

◆ SCIPlpiExactIsDualInfeasible()

◆ SCIPlpiExactIsDualFeasible()

◆ SCIPlpiExactIsOptimal()

◆ SCIPlpiExactIsStable()

◆ SCIPlpiExactIsObjlimExc()

◆ SCIPlpiExactIsIterlimExc()

◆ SCIPlpiExactIsTimelimExc()

◆ SCIPlpiExactGetInternalStatus()

◆ SCIPlpiExactIgnoreInstability()