SPxPricer Class Reference

Abstract pricer base class.Class SPxPricer is a pure virtual class defining the interface for pricer classes to be used by SoPlex. The pricer's task is to select a vector to enter or leave the simplex basis, depending on the chosen simplex type. More...

#include <spxpricer.h>

Inheritance diagram for SPxPricer:

Public Member Functions
Initialization
virtual const char *	getName () const
	get name of pricer.
virtual void	load (SPxSolver *p_solver)
	loads LP.
virtual void	clear ()
	unloads LP.
virtual SPxSolver *	solver () const
	returns loaded SPxSolver object.
virtual Real	epsilon () const
	returns violation bound theeps.
virtual void	setEpsilon (Real eps)
	sets violation bound.
virtual void	setType (SPxSolver::Type)
	sets pricing type.
virtual void	setRep (SPxSolver::Representation)
	sets basis representation.
Pivoting
virtual int	selectLeave ()=0
	returns selected index to leave basis.
virtual void	left4 (int, SPxId)
	performs leaving pivot.
virtual SPxId	selectEnter ()=0
	selects Id to enter basis.
virtual void	entered4 (SPxId, int)
	performs entering pivot.
Extension
virtual void	addedVecs (int)
	n vectors have been added to loaded LP.
virtual void	addedCoVecs (int)
	n covectors have been added to loaded LP.
Shrinking
virtual void	removedVec (int)
	vector i was removed from loaded LP.
virtual void	removedVecs (const int *)
	vectors given by perm have been removed from loaded LP.
virtual void	removedCoVec (int)
	covector i was removed from loaded LP.
virtual void	removedCoVecs (const int *)
	covectors given by perm have been removed from loaded LP.
Debugging
virtual bool	isConsistent () const
Constructors / Destructors
	SPxPricer (const char *p_name)
	constructor
	SPxPricer (const SPxPricer &old)
	copy constructor
SPxPricer &	operator= (const SPxPricer &rhs)
	assignment operator
virtual	~SPxPricer ()
	destructor.
virtual SPxPricer *	clone () const =0
	clone function for polymorphism

Protected Attributes
Data
const char *	m_name
	name of the pricer
SPxSolver *	thesolver
	the solver
Real	theeps
	violation bound

Detailed Description

Abstract pricer base class.

Class SPxPricer is a pure virtual class defining the interface for pricer classes to be used by SoPlex. The pricer's task is to select a vector to enter or leave the simplex basis, depending on the chosen simplex type.

An SPxPricer first loads the SoPlex object for which pricing is to be performed. Then, depending of the SPxSolver::Type, methods selectEnter() and entered4() (for entering Simplex) or selectLeave() and left4() (for leaving Simplex) are called by SoPlex. The SPxPricer object is informed of a change of the SPxSolver::Type by calling method setType().

Definition at line 49 of file spxpricer.h.

Constructor & Destructor Documentation

SPxPricer ( const char *  p_name )

explicit

constructor

Definition at line 225 of file spxpricer.h.

SPxPricer

(

const SPxPricer &

old

)

copy constructor

Definition at line 232 of file spxpricer.h.

virtual ~SPxPricer ( )

virtual

destructor.

Definition at line 254 of file spxpricer.h.

References SPxPricer::m_name, and SPxPricer::thesolver.

Member Function Documentation

virtual void addedCoVecs ( int  )

virtual

n covectors have been added to loaded LP.

Reimplemented in SPxSteepPR, SPxWeightPR, SPxDevexPR, and SPxHybridPR.

Definition at line 187 of file spxpricer.h.

Referenced by SPxHybridPR::addedCoVecs().

virtual void addedVecs ( int  )

virtual

n vectors have been added to loaded LP.

Reimplemented in SPxSteepPR, SPxWeightPR, SPxDevexPR, and SPxHybridPR.

Definition at line 184 of file spxpricer.h.

Referenced by SPxHybridPR::addedVecs().

virtual void clear ( )

virtual

unloads LP.

Reimplemented in SPxSteepPR, and SPxHybridPR.

Definition at line 84 of file spxpricer.h.

References SPxPricer::thesolver.

Referenced by SPxHybridPR::clear(), SPxSolver::loadLP(), SPxSolver::read(), SPxSolver::reLoad(), SPxSolver::setPricer(), and SPxSolver::SPxSolver().

virtual SPxPricer* clone ( ) const

pure virtual

clone function for polymorphism

Implemented in SPxHybridPR, SPxSteepPR, SPxWeightPR, SPxParMultPR, SPxDevexPR, SPxDantzigPR, and SPxSteepExPR.

Referenced by SPxSolver::operator=(), and SPxSolver::SPxSolver().

virtual void entered4 ( SPxId  , int    )

virtual

performs entering pivot.

Method entered4() is called after each simplex iteration in ENTER mode. It informs the SPxPricer that variable id has entered at the n 'th position. When being called, all vectors of SoPlex involved in such an entering update are setup correctly and may be accessed via the corresponding methods (fVec(), pVec(), etc.). In general, argument id will be the one returned by the SPxPricer at the previous call to selectEnter(). However, one can not rely on this.

Reimplemented in SPxSteepPR, SPxDevexPR, and SPxHybridPR.

Definition at line 175 of file spxpricer.h.

Referenced by SPxHybridPR::entered4(), and SPxSolver::fpsolve().

virtual Real epsilon ( ) const

virtual

returns violation bound theeps.

Definition at line 96 of file spxpricer.h.

References SPxPricer::theeps.

Referenced by SPxWeightPR::computeCP(), SPxWeightPR::computeRP(), SPxSolver::fpsolve(), and SPxSolver::precisionReached().

virtual const char* getName ( ) const

virtual

get name of pricer.

Definition at line 70 of file spxpricer.h.

References SPxPricer::m_name.

Referenced by get_pricer(), SPxHybridPR::setType(), and SPxSolver::writeState().

virtual bool isConsistent ( ) const

virtual

Reimplemented in SPxSteepPR, SPxWeightPR, SPxDevexPR, and SPxHybridPR.

Definition at line 211 of file spxpricer.h.

References SPxPricer::thesolver.

Referenced by SPxHybridPR::isConsistent(), and SPxPricer::operator=().

virtual void left4 ( int  , SPxId    )

virtual

performs leaving pivot.

Method left4() is called after each simplex iteration in LEAVE mode. It informs the SPxPricer that the n 'th variable has left the basis for id to come in at this position. When being called, all vectors of SoPlex involved in such an entering update are setup correctly and may be accessed via the corresponding methods (fVec(), pVec(), etc.). In general, argument n will be the one returned by the SPxPricer at the previous call to selectLeave(). However, one can not rely on this.

Reimplemented in SPxSteepPR, SPxDevexPR, and SPxHybridPR.

Definition at line 147 of file spxpricer.h.

Referenced by SPxSolver::fpsolve(), and SPxHybridPR::left4().

virtual void load ( SPxSolver *  p_solver )

virtual

loads LP.

Loads the solver and LP for which pricing steps are to be performed.

Reimplemented in SPxSteepPR, SPxWeightPR, SPxParMultPR, SPxDevexPR, and SPxHybridPR.

Definition at line 78 of file spxpricer.h.

References SPxPricer::thesolver.

Referenced by SPxSolver::init(), SPxSolver::operator=(), SPxSolver::setPricer(), and SPxSolver::SPxSolver().

SPxPricer& operator=

(

const SPxPricer &

rhs

)

assignment operator

Definition at line 239 of file spxpricer.h.

References SPxPricer::isConsistent(), SPxPricer::m_name, SPxPricer::theeps, and SPxPricer::thesolver.

Referenced by SPxDantzigPR::operator=(), SPxParMultPR::operator=(), SPxDevexPR::operator=(), SPxWeightPR::operator=(), SPxHybridPR::operator=(), and SPxSteepPR::operator=().

virtual void removedCoVec ( int  )

virtual

covector i was removed from loaded LP.

Reimplemented in SPxSteepPR, and SPxWeightPR.

Definition at line 201 of file spxpricer.h.

virtual void removedCoVecs ( const int *  )

virtual

covectors given by perm have been removed from loaded LP.

Definition at line 204 of file spxpricer.h.

virtual void removedVec ( int  )

virtual

vector i was removed from loaded LP.

Reimplemented in SPxSteepPR, and SPxWeightPR.

Definition at line 195 of file spxpricer.h.

Referenced by SPxSolver::doRemoveCol(), and SPxSolver::doRemoveRow().

virtual void removedVecs ( const int *  )

virtual

vectors given by perm have been removed from loaded LP.

Definition at line 198 of file spxpricer.h.

Referenced by SPxSolver::doRemoveCols(), and SPxSolver::doRemoveRows().

virtual SPxId selectEnter ( )

pure virtual

selects Id to enter basis.

Selects the SPxId of a vector to enter the basis. The selected id, must not represent a basic index (i.e. solver()->isBasic(id) must be false). However, the corresponding test value needs not to be less than -epsilon(). If not, SoPlex will discard the pivot.

Note: When method selectEnter() is called by the loaded SoPlex object, all values from coTest() are up to date. However, whether the elements of test() are up to date depends on the SPxSolver::Pricing type.

Implemented in SPxSteepPR, SPxWeightPR, SPxDevexPR, SPxParMultPR, SPxDantzigPR, and SPxHybridPR.

Referenced by SPxSolver::fpsolve(), and SPxHybridPR::selectEnter().

virtual int selectLeave ( )

pure virtual

returns selected index to leave basis.

Selects the index of a vector to leave the basis. The selected index i, say, must be in the range 0 <= i < solver()->dim() and its tested value must fullfill solver()->test()[i] < -epsilon().

Implemented in SPxSteepPR, SPxWeightPR, SPxDevexPR, SPxParMultPR, SPxDantzigPR, and SPxHybridPR.

Referenced by SPxSolver::fpsolve(), and SPxHybridPR::selectLeave().

virtual void setEpsilon ( Real  eps )

virtual

sets violation bound.

Inequality violations are accepted, if their size is less than eps.

Reimplemented in SPxHybridPR.

Definition at line 104 of file spxpricer.h.

References SPxPricer::theeps.

Referenced by SPxSolver::fpsolve(), and SPxHybridPR::setEpsilon().

virtual void setRep ( SPxSolver::Representation  )

virtual

sets basis representation.

Informs pricer about (a change of) the loaded SoPlex's Representation.

Reimplemented in SPxSteepPR, SPxWeightPR, SPxDevexPR, and SPxHybridPR.

Definition at line 122 of file spxpricer.h.

Referenced by SPxSolver::initRep(), and SPxHybridPR::setRep().

virtual void setType ( SPxSolver::Type  )

virtual

sets pricing type.

Informs pricer about (a change of) the loaded SoPlex's Type. In the sequel, only the corresponding select methods may be called.

Reimplemented in SPxSteepPR, SPxWeightPR, SPxParMultPR, SPxDevexPR, and SPxHybridPR.

Definition at line 115 of file spxpricer.h.

Referenced by SPxSolver::fpsolve(), and SPxHybridPR::setType().

virtual SPxSolver* solver ( ) const

virtual

returns loaded SPxSolver object.

Definition at line 90 of file spxpricer.h.

References SPxPricer::thesolver.

Referenced by SPxWeightPR::addedCoVecs(), SPxWeightPR::addedVecs(), SPxWeightPR::computeCP(), SPxWeightPR::computeLeavePenalty(), SPxWeightPR::computeRP(), SPxSolver::fpsolve(), SPxSolver::initRep(), SPxHybridPR::isConsistent(), SPxWeightPR::isConsistent(), SPxWeightPR::load(), SPxWeightPR::removedCoVec(), SPxWeightPR::removedCoVecs(), SPxWeightPR::removedVec(), SPxWeightPR::removedVecs(), SPxWeightPR::selectEnter(), and SPxWeightPR::selectLeave().

Member Data Documentation

const char* m_name

protected

name of the pricer

Definition at line 57 of file spxpricer.h.

Referenced by SPxPricer::getName(), SPxPricer::operator=(), and SPxPricer::~SPxPricer().

Real theeps

protected

violation bound

Definition at line 61 of file spxpricer.h.

Referenced by SPxPricer::epsilon(), SPxSteepPR::left4(), SPxDevexPR::left4X(), SPxPricer::operator=(), SPxParMultPR::selectEnter(), SPxDevexPR::selectEnter(), SPxWeightPR::selectEnter(), SPxDantzigPR::selectEnterDenseCoDim(), SPxSteepPR::selectEnterDenseCoDim(), SPxDantzigPR::selectEnterDenseDim(), SPxSteepPR::selectEnterDenseDim(), SPxDantzigPR::selectEnterSparseCoDim(), SPxSteepPR::selectEnterSparseCoDim(), SPxDantzigPR::selectEnterSparseDim(), SPxSteepPR::selectEnterSparseDim(), SPxDantzigPR::selectEnterX(), SPxDantzigPR::selectLeave(), SPxParMultPR::selectLeave(), SPxDevexPR::selectLeave(), SPxWeightPR::selectLeave(), SPxSteepPR::selectLeave(), SPxDantzigPR::selectLeavePart(), SPxSteepPR::selectLeavePart(), SPxDantzigPR::selectLeaveSparse(), SPxSteepPR::selectLeaveSparse(), and SPxPricer::setEpsilon().

SPxSolver* thesolver

protected

the solver

Definition at line 59 of file spxpricer.h.

Referenced by SPxDevexPR::addedCoVecs(), SPxSteepPR::addedCoVecs(), SPxDevexPR::addedVecs(), SPxSteepPR::addedVecs(), SPxHybridPR::clear(), SPxPricer::clear(), SPxSteepPR::clear(), SPxWeightPR::computeLeavePenalty(), SPxSteepPR::entered4(), SPxDevexPR::entered4X(), SPxHybridPR::isConsistent(), SPxDevexPR::isConsistent(), SPxPricer::isConsistent(), SPxSteepPR::isConsistent(), SPxSteepPR::left4(), SPxDevexPR::left4X(), SPxHybridPR::load(), SPxPricer::load(), SPxDevexPR::load(), SPxParMultPR::load(), SPxWeightPR::load(), SPxSteepPR::load(), SPxPricer::operator=(), SPxSteepPR::removedCoVec(), SPxSteepPR::removedCoVecs(), SPxSteepPR::removedVec(), SPxSteepPR::removedVecs(), SPxDantzigPR::selectEnter(), SPxParMultPR::selectEnter(), SPxDevexPR::selectEnter(), SPxSteepPR::selectEnter(), SPxDantzigPR::selectEnterDenseCoDim(), SPxDevexPR::selectEnterDenseCoDim(), SPxSteepPR::selectEnterDenseCoDim(), SPxDantzigPR::selectEnterDenseDim(), SPxDevexPR::selectEnterDenseDim(), SPxSteepPR::selectEnterDenseDim(), SPxDantzigPR::selectEnterSparseCoDim(), SPxDevexPR::selectEnterSparseCoDim(), SPxSteepPR::selectEnterSparseCoDim(), SPxDantzigPR::selectEnterSparseDim(), SPxDevexPR::selectEnterSparseDim(), SPxSteepPR::selectEnterSparseDim(), SPxDantzigPR::selectEnterX(), SPxDevexPR::selectEnterX(), SPxSteepPR::selectEnterX(), SPxDantzigPR::selectLeave(), SPxParMultPR::selectLeave(), SPxDevexPR::selectLeave(), SPxWeightPR::selectLeave(), SPxSteepPR::selectLeave(), SPxDantzigPR::selectLeavePart(), SPxDevexPR::selectLeavePart(), SPxSteepPR::selectLeavePart(), SPxDantzigPR::selectLeaveSparse(), SPxDevexPR::selectLeaveSparse(), SPxSteepPR::selectLeaveSparse(), SPxDevexPR::selectLeaveX(), SPxDevexPR::setRep(), SPxSteepPR::setRep(), SPxHybridPR::setType(), SPxParMultPR::setType(), SPxWeightPR::setType(), SPxSteepPR::setType(), SPxSteepPR::setupPrefs(), SPxSteepPR::setupPrefsX(), SPxSteepPR::setupWeights(), SPxPricer::solver(), and SPxPricer::~SPxPricer().