This is the Clp interface to CoinPresolve. More...

#include <ClpPresolve.hpp>

Public Member Functions
Main Constructor, destructor
	ClpPresolve ()
	Default constructor.
virtual	~ClpPresolve ()
	Virtual destructor.
presolve - presolves a model, transforming the model
and saving information in the ClpPresolve object needed for postsolving. This underlying (protected) method is virtual; the idea is that in the future, one could override this method to customize how the various presolve techniques are applied. This version of presolve returns a pointer to a new presolved model. NULL if infeasible or unbounded. This should be paired with postsolve below. The advantage of going back to original model is that it will be exactly as it was i.e. 0.0 will not become 1.0e-19. If keepIntegers is true then bounds may be tightened in original. Bounds will be moved by up to feasibilityTolerance to try and stay feasible. Names will be dropped in presolved model if asked
ClpSimplex *	presolvedModel (ClpSimplex &si, double feasibilityTolerance=0.0, bool keepIntegers=true, int numberPasses=5, bool dropNames=false, bool doRowObjective=false, const char prohibitedRows=NULL, const char prohibitedColumns=NULL)
int	presolvedModelToFile (ClpSimplex &si, std::string fileName, double feasibilityTolerance=0.0, bool keepIntegers=true, int numberPasses=5, bool dropNames=false, bool doRowObjective=false)
	This version saves data in a file.
ClpSimplex *	model () const
	Return pointer to presolved model, Up to user to destroy.
ClpSimplex *	originalModel () const
	Return pointer to original model.
void	setOriginalModel (ClpSimplex *model)
	Set pointer to original model.
const int *	originalColumns () const
	return pointer to original columns
const int *	originalRows () const
	return pointer to original rows
void	setNonLinearValue (double value)
	"Magic" number.
double	nonLinearValue () const
bool	doDual () const
	Whether we want to do dual part of presolve.
void	setDoDual (bool doDual)
bool	doSingleton () const
	Whether we want to do singleton part of presolve.
void	setDoSingleton (bool doSingleton)
bool	doDoubleton () const
	Whether we want to do doubleton part of presolve.
void	setDoDoubleton (bool doDoubleton)
bool	doTripleton () const
	Whether we want to do tripleton part of presolve.
void	setDoTripleton (bool doTripleton)
bool	doTighten () const
	Whether we want to do tighten part of presolve.
void	setDoTighten (bool doTighten)
bool	doForcing () const
	Whether we want to do forcing part of presolve.
void	setDoForcing (bool doForcing)
bool	doImpliedFree () const
	Whether we want to do impliedfree part of presolve.
void	setDoImpliedFree (bool doImpliedfree)
bool	doDupcol () const
	Whether we want to do dupcol part of presolve.
void	setDoDupcol (bool doDupcol)
bool	doDuprow () const
	Whether we want to do duprow part of presolve.
void	setDoDuprow (bool doDuprow)
bool	doSingletonColumn () const
	Whether we want to do singleton column part of presolve.
void	setDoSingletonColumn (bool doSingleton)
bool	doGubrow () const
	Whether we want to do gubrow part of presolve.
void	setDoGubrow (bool doGubrow)
bool	doTwoxTwo () const
	Whether we want to do twoxtwo part of presolve.
void	setDoTwoxtwo (bool doTwoxTwo)
int	presolveActions () const
	Set whole group.
void	setPresolveActions (int action)
void	setSubstitution (int value)
	Substitution level.
void	statistics ()
	Asks for statistics.
int	presolveStatus () const
	Return presolve status (0,1,2)
postsolve - postsolve the problem. If the problem
has not been solved to optimality, there are no guarantees. If you are using an algorithm like simplex that has a concept of "basic" rows/cols, then set updateStatus Note that if you modified the original problem after presolving, then you must ``undo'' these modifications before calling postsolve. This version updates original
virtual void	postsolve (bool updateStatus=true)
void	destroyPresolve ()
	Gets rid of presolve actions (e.g.when infeasible)
private or protected data
virtual const CoinPresolveAction *	presolve (CoinPresolveMatrix *prob)
	If you want to apply the individual presolve routines differently, or perhaps add your own to the mix, define a derived class and override this method.
virtual void	postsolve (CoinPostsolveMatrix &prob)
	Postsolving is pretty generic; just apply the transformations in reverse order.
virtual ClpSimplex *	gutsOfPresolvedModel (ClpSimplex originalModel, double feasibilityTolerance, bool keepIntegers, int numberPasses, bool dropNames, bool doRowObjective, const char prohibitedRows=NULL, const char *prohibitedColumns=NULL)
	This is main part of Presolve.

Detailed Description

This is the Clp interface to CoinPresolve.

Definition at line 15 of file ClpPresolve.hpp.

Constructor & Destructor Documentation

ClpPresolve::ClpPresolve ( )

Default constructor.

virtual ClpPresolve::~ClpPresolve ( ) [virtual]

Virtual destructor.

Member Function Documentation

ClpSimplex* ClpPresolve::presolvedModel	(	ClpSimplex &	si,
		double	feasibilityTolerance = `0.0`,
		bool	keepIntegers = `true`,
		int	numberPasses = `5`,
		bool	dropNames = `false`,
		bool	doRowObjective = `false`,
		const char *	prohibitedRows = `NULL`,
		const char *	prohibitedColumns = `NULL`
	)

int ClpPresolve::presolvedModelToFile	(	ClpSimplex &	si,
		std::string	fileName,
		double	feasibilityTolerance = `0.0`,
		bool	keepIntegers = `true`,
		int	numberPasses = `5`,
		bool	dropNames = `false`,
		bool	doRowObjective = `false`
	)

This version saves data in a file.

The passed in model is updated to be presolved model. Returns non-zero if infeasible

ClpSimplex* ClpPresolve::model ( ) const

Return pointer to presolved model, Up to user to destroy.

ClpSimplex* ClpPresolve::originalModel ( ) const

Return pointer to original model.

void ClpPresolve::setOriginalModel ( ClpSimplex * model )

Set pointer to original model.

const int* ClpPresolve::originalColumns ( ) const

return pointer to original columns

const int* ClpPresolve::originalRows ( ) const

return pointer to original rows

void ClpPresolve::setNonLinearValue ( double value ) [inline]

"Magic" number.

If this is non-zero then any elements with this value may change and so presolve is very limited in what can be done to the row and column. This is for non-linear problems.

Definition at line 76 of file ClpPresolve.hpp.

double ClpPresolve::nonLinearValue ( ) const [inline]

Definition at line 79 of file ClpPresolve.hpp.

bool ClpPresolve::doDual ( ) const [inline]

Whether we want to do dual part of presolve.

Definition at line 83 of file ClpPresolve.hpp.

void ClpPresolve::setDoDual ( bool doDual ) [inline]

Definition at line 86 of file ClpPresolve.hpp.

bool ClpPresolve::doSingleton ( ) const [inline]

Whether we want to do singleton part of presolve.

Definition at line 91 of file ClpPresolve.hpp.

void ClpPresolve::setDoSingleton ( bool doSingleton ) [inline]

Definition at line 94 of file ClpPresolve.hpp.

bool ClpPresolve::doDoubleton ( ) const [inline]

Whether we want to do doubleton part of presolve.

Definition at line 99 of file ClpPresolve.hpp.

void ClpPresolve::setDoDoubleton ( bool doDoubleton ) [inline]

Definition at line 102 of file ClpPresolve.hpp.

bool ClpPresolve::doTripleton ( ) const [inline]

Whether we want to do tripleton part of presolve.

Definition at line 107 of file ClpPresolve.hpp.

void ClpPresolve::setDoTripleton ( bool doTripleton ) [inline]

Definition at line 110 of file ClpPresolve.hpp.

bool ClpPresolve::doTighten ( ) const [inline]

Whether we want to do tighten part of presolve.

Definition at line 115 of file ClpPresolve.hpp.

void ClpPresolve::setDoTighten ( bool doTighten ) [inline]

Definition at line 118 of file ClpPresolve.hpp.

bool ClpPresolve::doForcing ( ) const [inline]

Whether we want to do forcing part of presolve.

Definition at line 123 of file ClpPresolve.hpp.

void ClpPresolve::setDoForcing ( bool doForcing ) [inline]

Definition at line 126 of file ClpPresolve.hpp.

bool ClpPresolve::doImpliedFree ( ) const [inline]

Whether we want to do impliedfree part of presolve.

Definition at line 131 of file ClpPresolve.hpp.

void ClpPresolve::setDoImpliedFree ( bool doImpliedfree ) [inline]

Definition at line 134 of file ClpPresolve.hpp.

bool ClpPresolve::doDupcol ( ) const [inline]

Whether we want to do dupcol part of presolve.

Definition at line 139 of file ClpPresolve.hpp.

void ClpPresolve::setDoDupcol ( bool doDupcol ) [inline]

Definition at line 142 of file ClpPresolve.hpp.

bool ClpPresolve::doDuprow ( ) const [inline]

Whether we want to do duprow part of presolve.

Definition at line 147 of file ClpPresolve.hpp.

void ClpPresolve::setDoDuprow ( bool doDuprow ) [inline]

Definition at line 150 of file ClpPresolve.hpp.

bool ClpPresolve::doSingletonColumn ( ) const [inline]

Whether we want to do singleton column part of presolve.

Definition at line 155 of file ClpPresolve.hpp.

void ClpPresolve::setDoSingletonColumn ( bool doSingleton ) [inline]

Definition at line 158 of file ClpPresolve.hpp.

bool ClpPresolve::doGubrow ( ) const [inline]

Whether we want to do gubrow part of presolve.

Definition at line 163 of file ClpPresolve.hpp.

void ClpPresolve::setDoGubrow ( bool doGubrow ) [inline]

Definition at line 166 of file ClpPresolve.hpp.

bool ClpPresolve::doTwoxTwo ( ) const [inline]

Whether we want to do twoxtwo part of presolve.

Definition at line 171 of file ClpPresolve.hpp.

void ClpPresolve::setDoTwoxtwo ( bool doTwoxTwo ) [inline]

Definition at line 174 of file ClpPresolve.hpp.

int ClpPresolve::presolveActions ( ) const [inline]

Set whole group.

Definition at line 179 of file ClpPresolve.hpp.

void ClpPresolve::setPresolveActions ( int action ) [inline]

Definition at line 182 of file ClpPresolve.hpp.

void ClpPresolve::setSubstitution ( int value ) [inline]

Substitution level.

Definition at line 186 of file ClpPresolve.hpp.

void ClpPresolve::statistics ( ) [inline]

Asks for statistics.

Definition at line 190 of file ClpPresolve.hpp.

int ClpPresolve::presolveStatus ( ) const

Return presolve status (0,1,2)

virtual void ClpPresolve::postsolve ( bool updateStatus = true ) [virtual]

void ClpPresolve::destroyPresolve ( )

Gets rid of presolve actions (e.g.when infeasible)

virtual const CoinPresolveAction* ClpPresolve::presolve ( CoinPresolveMatrix * prob ) [protected, virtual]

If you want to apply the individual presolve routines differently, or perhaps add your own to the mix, define a derived class and override this method.

virtual void ClpPresolve::postsolve ( CoinPostsolveMatrix & prob ) [protected, virtual]

Postsolving is pretty generic; just apply the transformations in reverse order.

You will probably only be interested in overriding this method if you want to add code to test for consistency while debugging new presolve techniques.

virtual ClpSimplex* ClpPresolve::gutsOfPresolvedModel	(	ClpSimplex *	originalModel,
		double	feasibilityTolerance,
		bool	keepIntegers,
		int	numberPasses,
		bool	dropNames,
		bool	doRowObjective,
		const char *	prohibitedRows = `NULL`,
		const char *	prohibitedColumns = `NULL`
	)		`[protected, virtual]`

This is main part of Presolve.

The documentation for this class was generated from the following file:

src/ClpPresolve.hpp

Public Member Functions

private or protected data

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation