Scippy

    SCIP

    Solving Constraint Integer Programs

    Exact LP Solver Interface

    Detailed Description

    methods 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 methods 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
    SCIP_VAR ** x
    Definition: circlepacking.c:63
    Rational & max(Rational &r1, Rational &r2)
    Rational & min(Rational &r1, Rational &r2)

    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 417 of file lpiexact_qsoex.c.

    ◆ SCIPlpiExactPrintInfo()

    void SCIPlpiExactPrintInfo ( SCIP_LPIEXACT lpi)

    prints additional lpiexact internal info

    Parameters
    lpiLP interface structure

    ◆ SCIPlpiExactGetExternalCodeDesc()

    const char * SCIPlpiExactGetExternalCodeDesc ( void  )

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

    Definition at line 431 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
    lpipointer 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

    ◆ SCIPlpiExactCreate()

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

    creates an LP problem object

    Parameters
    lpipointer to an LP interface structure
    messagehdlrmessage handler to use for printing messages, or NULL
    nameproblem name
    objsenobjective sense

    Definition at line 126 of file lpiexact_none.c.

    References BMSallocMemory, BMSallocMemoryCPP, FALSE, FEASTOL, 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
    lpipointer to an LP interface structure

    Definition at line 147 of file lpiexact_none.c.

    References 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
    lpiLP interface structure
    objsenobjective sense
    ncolsnumber of columns
    objobjective function values of columns
    lblower bounds of columns
    ubupper bounds of columns
    colnamescolumn names, or NULL
    nrowsnumber of rows
    lhsleft hand sides of rows
    rhsright hand sides of rows
    rownamesrow names, or NULL
    nnonznumber of nonzero elements in the constraint matrix
    begstart index of each column in ind- and val-array
    indrow indices of constraint matrix entries
    valvalues of constraint matrix entries

    Definition at line 170 of file lpiexact_none.c.

    References invalidateSolution(), SCIP_LPiExact::messagehdlr, SCIP_LPiExact::ncols, SCIP_LPiExact::nrows, NULL, 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
    lpiLP interface structure
    ncolsnumber of columns to be added
    objobjective function values of new columns
    lblower bounds of new columns
    ubupper bounds of new columns
    colnamescolumn names, or NULL
    nnonznumber of nonzero elements to be added to the constraint matrix
    begstart index of each column in ind- and val-array, or NULL if nnonz == 0
    indrow indices of constraint matrix entries, or NULL if nnonz == 0
    valvalues of constraint matrix entries, or NULL if nnonz == 0

    Definition at line 215 of file lpiexact_none.c.

    References invalidateSolution(), SCIP_LPiExact::messagehdlr, SCIP_LPiExact::ncols, NULL, 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
    lpiLP interface structure
    firstcolfirst column to be deleted
    lastcollast column to be deleted

    Definition at line 245 of file lpiexact_none.c.

    References 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
    lpiLP interface structure
    dstatdeletion status of columns input: 1 if column should be deleted, 0 if not output: new position of column, -1 if column was deleted

    ◆ 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
    lpiLP interface structure
    nrowsnumber of rows to be added
    lhsleft hand sides of new rows
    rhsright hand sides of new rows
    rownamesrow names, or NULL
    nnonznumber of nonzero elements to be added to the constraint matrix
    begstart index of each row in ind- and val-array, or NULL if nnonz == 0
    indcolumn indices of constraint matrix entries, or NULL if nnonz == 0
    valvalues of constraint matrix entries, or NULL if nnonz == 0

    Definition at line 261 of file lpiexact_none.c.

    References 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
    lpiLP interface structure
    firstrowfirst row to be deleted
    lastrowlast row to be deleted

    Definition at line 287 of file lpiexact_none.c.

    References 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
    lpiLP interface structure
    dstatdeletion 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 invalidateSolution(), SCIP_LPiExact::messagehdlr, SCIP_LPiExact::nrows, NULL, SPxexSCIP::preStrongbranchingBasisFreed(), SCIP_OKAY, SCIPdebugMessage, SOPLEX_TRY, and SCIP_LPiExact::spx.

    Referenced by SCIPlpExactDelRowset().

    ◆ SCIPlpiExactClear()

    ◆ 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
    lpiLP interface structure
    ncolsnumber of columns to change bounds for
    indcolumn indices or NULL if ncols is zero
    lbvalues for the new lower bounds or NULL if ncols is zero
    ubvalues for the new upper bounds or NULL if ncols is zero

    Definition at line 349 of file lpiexact_none.c.

    References 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
    lpiLP interface structure
    nrowsnumber of rows to change sides for
    indrow indices
    lhsnew values for left hand sides
    rhsnew values for right hand sides

    Definition at line 362 of file lpiexact_none.c.

    References 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
    lpiLP interface structure
    rowrow number of coefficient to change
    colcolumn number of coefficient to change
    newvalnew value of coefficient

    Definition at line 379 of file lpiexact_none.c.

    References 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
    lpiLP interface structure
    objsennew objective sense

    Definition at line 391 of file lpiexact_none.c.

    References 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
    lpiLP interface structure
    ncolsnumber of columns to change objective value for
    indcolumn indices to change objective value for
    objnew objective values for columns

    Definition at line 401 of file lpiexact_none.c.

    References invalidateSolution(), SCIP_LPiExact::messagehdlr, NULL, 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
    lpiLP interface structure
    rowrow number to scale
    scalevalscaling 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
    lpiLP interface structure
    colcolumn number to scale
    scalevalscaling multiplier

    ◆ SCIPlpiExactGetNRows()

    SCIP_RETCODE SCIPlpiExactGetNRows ( SCIP_LPIEXACT lpi,
    int *  nrows 
    )

    gets the number of rows in the LP

    Parameters
    lpiLP interface structure
    nrowspointer to store the number of rows

    Definition at line 423 of file lpiexact_none.c.

    References 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
    lpiLP interface structure
    ncolspointer to store the number of cols

    Definition at line 438 of file lpiexact_none.c.

    References 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
    lpiLP interface structure
    objsenpointer to store objective sense

    Definition at line 545 of file lpiexact_none.c.

    References 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
    lpiLP interface structure
    nnonzpointer to store the number of nonzeros

    Definition at line 453 of file lpiexact_none.c.

    References errorMessage(), 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
    lpiLP interface structure
    firstcolfirst column to get from LP
    lastcollast column to get from LP
    lbbuffer to store the lower bound vector, or NULL
    ubbuffer to store the upper bound vector, or NULL
    nnonzpointer to store the number of nonzero elements returned, or NULL
    begbuffer to store start index of each column in ind- and val-array, or NULL
    indbuffer to store row indices of constraint matrix entries, or NULL
    valbuffer to store values of constraint matrix entries, or NULL

    Definition at line 468 of file lpiexact_none.c.

    References errorMessage(), 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
    lpiLP interface structure
    firstrowfirst row to get from LP
    lastrowlast row to get from LP
    lhsbuffer to store left hand side vector, or NULL
    rhsbuffer to store right hand side vector, or NULL
    nnonzpointer to store the number of nonzero elements returned, or NULL
    begbuffer to store start index of each row in ind- and val-array, or NULL
    indbuffer to store column indices of constraint matrix entries, or NULL
    valbuffer to store values of constraint matrix entries, or NULL

    Definition at line 488 of file lpiexact_none.c.

    References errorMessage(), FALSE, 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
    lpiLP interface structure
    firstcolfirst column to get name from LP
    lastcollast column to get name from LP
    colnamespointers to column names (of size at least lastcol-firstcol+1) or NULL if namestoragesize is zero
    namestoragestorage for col names or NULL if namestoragesize is zero
    namestoragesizesize of namestorage (if 0, storageleft returns the storage needed)
    storageleftamount 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 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
    lpiLP interface structure
    firstrowfirst row to get name from LP
    lastrowlast row to get name from LP
    rownamespointers to row names (of size at least lastrow-firstrow+1) or NULL if namestoragesize is zero
    namestoragestorage for row names or NULL if namestoragesize is zero
    namestoragesizesize of namestorage (if 0, -storageleft returns the storage needed)
    storageleftamount 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 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
    lpiLP interface structure
    firstcolfirst column to get objective coefficient for
    lastcollast column to get objective coefficient for
    valsarray to store objective coefficients

    Definition at line 555 of file lpiexact_none.c.

    References errorMessage(), 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
    lpiLP interface structure
    firstcolfirst column to get objective value for
    lastcollast column to get objective value for
    lbsarray to store lower bound values, or NULL
    ubsarray to store upper bound values, or NULL

    Definition at line 570 of file lpiexact_none.c.

    References errorMessage(), 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
    lpiLP interface structure
    firstrowfirst row to get sides for
    lastrowlast row to get sides for
    lhssarray to store left hand side values, or NULL
    rhssarray to store right hand side values, or NULL

    Definition at line 585 of file lpiexact_none.c.

    References errorMessage(), 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
    lpiLP interface structure
    rowrow number of coefficient
    colcolumn number of coefficient
    valpointer to store the value of the coefficient

    Definition at line 600 of file lpiexact_none.c.

    References 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
    lpiLP interface structure

    Definition at line 624 of file lpiexact_none.c.

    References 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
    lpiLP interface structure

    Definition at line 634 of file lpiexact_none.c.

    References 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
    lpiLP interface structure
    crossoverperform crossover

    Definition at line 644 of file lpiexact_none.c.

    References errorMessage(), NULL, 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
    lpiLP interface structure

    Definition at line 655 of file lpiexact_none.c.

    References 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
    lpiLP interface structure

    Definition at line 666 of file lpiexact_none.c.

    References 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
    lpiLP interface structure
    colcolumn to apply strong branching on
    psolcurrent primal solution value of column
    itlimiteration limit for strong branchings
    downstores dual bound after branching column down
    upstores dual bound after branching column up
    downvalidstores whether the returned down value is a valid dual bound; otherwise, it can only be used as an estimate value
    upvalidstores whether the returned up value is a valid dual bound; otherwise, it can only be used as an estimate value
    iterstores total number of strong branching iterations, or -1; may be NULL

    ◆ SCIPlpiExactWasSolved()

    SCIP_Bool SCIPlpiExactWasSolved ( SCIP_LPIEXACT lpi)

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

    Parameters
    lpiLP interface structure

    Definition at line 687 of file lpiexact_none.c.

    References errorMessageAbort(), FALSE, NULL, 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

    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
    primalfeasibleand
    dualfeasibleshould 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
    lpiLP interface structure
    primalfeasiblepointer to store primal feasibility status
    dualfeasiblepointer to store dual feasibility status

    Definition at line 706 of file lpiexact_none.c.

    References errorMessage(), NULL, 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
    lpiLP interface structure

    Definition at line 722 of file lpiexact_none.c.

    References errorMessageAbort(), FALSE, NULL, 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
    lpiLP interface structure

    Definition at line 734 of file lpiexact_none.c.

    References errorMessageAbort(), FALSE, NULL, 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
    lpiLP interface structure

    Definition at line 744 of file lpiexact_none.c.

    References errorMessageAbort(), FALSE, NULL, 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
    lpiLP interface structure

    Definition at line 754 of file lpiexact_none.c.

    References errorMessageAbort(), FALSE, NULL, 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
    lpiLP interface structure

    Definition at line 764 of file lpiexact_none.c.

    References errorMessageAbort(), FALSE, NULL, 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
    lpiLP interface structure

    Definition at line 776 of file lpiexact_none.c.

    References errorMessageAbort(), FALSE, NULL, 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
    lpiLP interface structure

    Definition at line 788 of file lpiexact_none.c.

    References errorMessageAbort(), FALSE, NULL, 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
    lpiLP interface structure

    Definition at line 798 of file lpiexact_none.c.

    References errorMessageAbort(), FALSE, NULL, 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
    lpiLP interface structure

    Definition at line 808 of file lpiexact_none.c.

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

    ◆ SCIPlpiExactIsDualFeasible()

    SCIP_Bool SCIPlpiExactIsDualFeasible ( SCIP_LPIEXACT lpi)

    returns TRUE iff LP is proven to be dual feasible

    Parameters
    lpiLP interface structure

    Definition at line 818 of file lpiexact_none.c.

    References errorMessageAbort(), FALSE, NULL, 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
    lpiLP interface structure

    Definition at line 828 of file lpiexact_none.c.

    References errorMessageAbort(), FALSE, NULL, 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
    lpiLP interface structure

    ◆ SCIPlpiExactIsObjlimExc()

    SCIP_Bool SCIPlpiExactIsObjlimExc ( SCIP_LPIEXACT lpi)

    returns TRUE iff the objective limit was reached

    Parameters
    lpiLP interface structure

    Definition at line 838 of file lpiexact_none.c.

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

    Referenced by lpExactFlushAndSolve().

    ◆ SCIPlpiExactIsIterlimExc()

    SCIP_Bool SCIPlpiExactIsIterlimExc ( SCIP_LPIEXACT lpi)

    returns TRUE iff the iteration limit was reached

    Parameters
    lpiLP interface structure

    Definition at line 848 of file lpiexact_none.c.

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

    Referenced by lpExactFlushAndSolve().

    ◆ SCIPlpiExactIsTimelimExc()

    SCIP_Bool SCIPlpiExactIsTimelimExc ( SCIP_LPIEXACT lpi)

    returns TRUE iff the time limit was reached

    Parameters
    lpiLP interface structure

    Definition at line 858 of file lpiexact_none.c.

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

    Referenced by lpExactFlushAndSolve().

    ◆ SCIPlpiExactGetInternalStatus()

    int SCIPlpiExactGetInternalStatus ( SCIP_LPIEXACT lpi)

    returns the internal solution status of the solver

    Parameters
    lpiLP interface structure

    Definition at line 868 of file lpiexact_none.c.

    References 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
    lpiLP interface structure
    successpointer to store, whether the instability could be ignored

    Definition at line 878 of file lpiexact_none.c.

    References errorMessage(), FALSE, NULL, 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
    lpiLP interface structure
    objvalstores the objective value

    Definition at line 890 of file lpiexact_none.c.

    References errorMessage(), NULL, 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

    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
    lpiLP interface structure
    objvalstores the objective value, may be NULL if not needed
    primsolprimal solution vector, may be NULL if not needed
    dualsoldual solution vector, may be NULL if not needed
    activityrow activity vector, may be NULL if not needed
    redcostreduced cost vector, may be NULL if not needed

    Definition at line 907 of file lpiexact_none.c.

    References errorMessage(), MAX, SCIP_LPiExact::messagehdlr, NULL, 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
    lpiLP interface structure
    rayprimal ray

    Definition at line 923 of file lpiexact_none.c.

    References 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
    lpiLP interface structure
    dualfarkasdual farkas row multipliers

    Definition at line 934 of file lpiexact_none.c.

    References 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
    lpiLP interface structure
    iterationspointer to store the number of iterations of the last solve call

    Definition at line 945 of file lpiexact_none.c.

    References 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
    lpiLP interface structure
    cstatarray to store column basis status, or NULL
    rstatarray to store row basis status, or NULL

    Definition at line 967 of file lpiexact_none.c.

    References errorMessage(), 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()

    ◆ 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
    lpiLP interface structure
    bindpointer to store basis indices ready to keep number of rows entries

    Definition at line 993 of file lpiexact_none.c.

    References 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
    lpiLP interface structure
    rrow number
    coefpointer to store the coefficients of the row
    indsarray to store the non-zero indices, or NULL
    nindspointer 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 errorMessage(), 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
    lpiLP interface structure
    ccolumn 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
    coefpointer to store the coefficients of the column
    indsarray to store the non-zero indices, or NULL
    nindspointer 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 errorMessage(), 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
    lpiLP interface structure
    rrow number
    binvrowrow in (A_B)^-1 from prior call to SCIPlpiExactGetBInvRow(), or NULL
    coefvector to return coefficients
    indsarray to store the non-zero indices, or NULL
    nindspointer to store the number of non-zero indices, or NULL (-1: if we do not store sparsity information)

    ◆ 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
    lpiLP interface structure
    ccolumn number
    coefvector to return coefficients
    indsarray to store the non-zero indices, or NULL
    nindspointer to store the number of non-zero indices, or NULL (-1: if we do not store sparsity information)

    ◆ SCIPlpiExactGetState()

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

    stores LPi state (like basis information) into lpistate object

    Parameters
    lpiLP interface structure
    blkmemblock memory
    lpistatepointer to LPi state information (like basis information)

    Definition at line 1061 of file lpiexact_none.c.

    References 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
    lpiLP interface structure
    blkmemblock memory
    lpistateLPi state information (like basis information), or NULL

    Definition at line 1078 of file lpiexact_none.c.

    References SCIP_LPiExact::cstat, ensureCstatMem(), ensureRstatMem(), errorMessage(), 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
    lpiLP interface structure

    Definition at line 1092 of file lpiexact_none.c.

    References 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
    lpiLP interface structure
    blkmemblock memory
    lpistatepointer to LPi state information (like basis information)

    Definition at line 1101 of file lpiexact_none.c.

    References 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
    lpiLP interface structure
    lpistateLP state information (like basis information), or NULL

    Definition at line 1114 of file lpiexact_none.c.

    References errorMessageAbort(), FALSE, NULL, 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
    lpiLP interface structure
    fnamefile name

    Definition at line 1125 of file lpiexact_none.c.

    References 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
    lpiLP interface structure
    fnamefile name

    Definition at line 1137 of file lpiexact_none.c.

    References 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
    lpiLP interface structure
    blkmemblock memory
    lpistateLPi state information (like basis information)
    useprestepshould approximate primal and dual solution first
    primalsolapproximate primal solution; or NULL to compute by exact LP solver
    dualsolapproximate dual solution; or NULL to compute by exact LP solver
    resultpointer to store whether given LPi state is dual feasible
    dualobjvalpointer to store dual objective value in case of dual feasibility

    ◆ SCIPlpiExactGetNorms()

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

    stores lpiexact pricing norms into lpiexactnorms object

    Parameters
    lpiLP interface structure
    blkmemblock memory
    lpinormspointer 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
    lpiLP interface structure
    blkmemblock memory
    lpinormsLPi pricing norms information, or NULL

    ◆ SCIPlpiExactFreeNorms()

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

    frees LPi pricing norms information

    Parameters
    lpiLP interface structure
    blkmemblock memory
    lpinormspointer to LPi pricing norms information, or NULL

    ◆ SCIPlpiExactGetIntpar()

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

    ◆ SCIPlpiExactSetIntpar()

    ◆ SCIPlpiExactGetRealpar()

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

    gets floating point parameter of LP

    Parameters
    lpiLP interface structure
    typeparameter number
    dvalbuffer to store the parameter value

    Definition at line 1182 of file lpiexact_none.c.

    References 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, 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
    lpiLP interface structure
    typeparameter number
    dvalparameter value

    Definition at line 1194 of file lpiexact_none.c.

    References SCIP_LPiExact::checkcondition, SCIP_LPiExact::conditionlimit, NULL, SCIP_LPPAR_CONDITIONLIMIT, SCIP_LPPAR_LPTILIM, SCIP_LPPAR_OBJLIM, SCIP_LPPAR_ROWREPSWITCH, SCIP_OKAY, SCIP_PARAMETERUNKNOWN, 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
    lpiLP interface structure
    infvalpointer 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
    lpiLP interface structure
    valgiven value

    ◆ SCIPlpiExactNegInfinity()

    void SCIPlpiExactNegInfinity ( SCIP_LPIEXACT lpi,
    SCIP_RATIONAL infval 
    )

    returns value treated as negative infinity in the LP solver

    Parameters
    lpiLP interface structure
    infvalpointer 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
    lpiLP interface structure
    valgiven value

    ◆ SCIPlpiExactInfinity()

    SCIP_Real SCIPlpiExactInfinity ( SCIP_LPIEXACT lpi)

    returns value treated as infinity in the LP solver

    Parameters
    lpiLP interface structure

    Definition at line 1216 of file lpiexact_none.c.

    References LPIINFINITY, NULL, 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
    lpiLP interface structure
    valthe value

    Definition at line 1225 of file lpiexact_none.c.

    References FALSE, LPIINFINITY, NULL, SCIPdebugMessage, SCIP_LPiExact::spx, and TRUE.

    Referenced by RsetSpxR(), and SCIPlpiExactSetState().

    ◆ SCIPlpiExactReadLP()

    SCIP_RETCODE SCIPlpiExactReadLP ( SCIP_LPIEXACT lpi,
    const char *  fname 
    )

    ◆ SCIPlpiExactWriteLP()

    SCIP_RETCODE SCIPlpiExactWriteLP ( SCIP_LPIEXACT lpi,
    const char *  fname 
    )

    writes LP to a file

    Parameters
    lpiLP interface structure
    fnamefile name

    Definition at line 1259 of file lpiexact_none.c.

    References 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
    lpiLP interface structure
    dimdimension of matrix
    cbegcolumn indices of matrix
    clencolumn lengths of matrix
    cindxrow index of entries
    ccoefcoef 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
    lpiLP interface structure
    dimdimension of matrix
    solsolution to system
    rhsrhs of system

    ◆ SCIPlpiExactSetIntegralityInformation()

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

    pass integrality information about variables to the solver

    Parameters
    lpipointer to an LP interface structure
    ncolslength of integrality array
    intInfointegrality array (0: continuous, 1: integer). May be NULL iff ncols is 0.

    Definition at line 794 of file lpiexact_spx.cpp.

    References 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 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 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.

    ◆ 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
    lpiLP interface structure
    dstatdeletion 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 invalidateSolution(), SCIP_LPiExact::messagehdlr, NULL, SPxexSCIP::preStrongbranchingBasisFreed(), SCIP_OKAY, SCIPdebugMessage, SOPLEX_TRY, and SCIP_LPiExact::spx.