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>

Classes
struct	IdxCompare
	Compare class to sort idx/val pairs, used for hypersparse pricing leaving. More...

struct	IdxElement

Public Types
enum	ViolationType { NOT_VIOLATED = 0, VIOLATED = 1, VIOLATED_AND_CHECKED = 2 }

Public Member Functions
Initialization
virtual const char *	getName () const
	get name of pricer. More...

virtual void	load (SPxSolverBase< R > *p_solver)
	loads LP. More...

virtual void	clear ()
	unloads LP. More...

virtual SPxSolverBase< R > *	solver () const
	returns loaded SPxSolverBase object. More...

virtual R	epsilon () const
	returns violation bound theeps. More...

virtual void	setEpsilon (R eps)
	sets violation bound. More...

virtual void	setType (typename SPxSolverBase< R >::Type)
	sets pricing type. More...

virtual void	setRep (typename SPxSolverBase< R >::Representation)
	sets basis representation. More...

Pivoting
virtual int	selectLeave ()=0
	returns selected index to leave basis. More...

virtual void	left4 (int, SPxId)
	performs leaving pivot. More...

virtual SPxId	selectEnter ()=0
	selects Id to enter basis. More...

virtual void	entered4 (SPxId, int)
	performs entering pivot. More...

Extension
virtual void	addedVecs (int)
	`n` vectors have been added to loaded LP. More...

virtual void	addedCoVecs (int)
	`n` covectors have been added to loaded LP. More...

Shrinking
virtual void	removedVec (int)
	vector `i` was removed from loaded LP. More...

virtual void	removedVecs (const int *)
	vectors given by `perm` have been removed from loaded LP. More...

virtual void	removedCoVec (int)
	covector `i` was removed from loaded LP. More...

virtual void	removedCoVecs (const int *)
	covectors given by `perm` have been removed from loaded LP. More...

Debugging
virtual bool	isConsistent () const

Constructors / Destructors
	SPxPricer (const char *p_name)
	constructor More...

	SPxPricer (const SPxPricer &old)
	copy constructor More...

SPxPricer &	operator= (const SPxPricer &rhs)
	assignment operator More...

virtual	~SPxPricer ()
	destructor. More...

virtual SPxPricer *	clone () const =0
	clone function for polymorphism More...

Protected Attributes
IdxCompare	compare

Data
const char *	m_name
	name of the pricer More...

SPxSolverBase< R > *	thesolver
	the solver More...

R	theeps
	violation bound More...

Detailed Description

template<class R>
class soplex::SPxPricer< R >

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 SPxSolverBase<R>::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 SPxSolverBase<R>::Type by calling method setType().

Definition at line 47 of file spxpricer.h.

Member Enumeration Documentation

◆ ViolationType

enum ViolationType

Enumerator
NOT_VIOLATED
VIOLATED
VIOLATED_AND_CHECKED

Definition at line 97 of file spxpricer.h.

Constructor & Destructor Documentation

◆ SPxPricer() [1/2]

SPxPricer ( const char * p_name )

explicit

constructor

Definition at line 267 of file spxpricer.h.

◆ SPxPricer() [2/2]

SPxPricer ( const SPxPricer< R > & old )

copy constructor

Definition at line 274 of file spxpricer.h.

◆ ~SPxPricer()

virtual ~SPxPricer ( )

virtual

destructor.

Definition at line 295 of file spxpricer.h.

References SPxPricer< R >::clone(), and SPxPricer< R >::thesolver.

Member Function Documentation

◆ addedCoVecs()

virtual void addedCoVecs ( int )

virtual

n covectors have been added to loaded LP.

Reimplemented in SPxSteepPR< R >, SPxWeightPR< R >, SPxDevexPR< R >, and SPxHybridPR< R >.

Definition at line 229 of file spxpricer.h.

◆ addedVecs()

virtual void addedVecs ( int )

virtual

n vectors have been added to loaded LP.

Reimplemented in SPxSteepPR< R >, SPxWeightPR< R >, SPxDevexPR< R >, and SPxHybridPR< R >.

Definition at line 226 of file spxpricer.h.

◆ clear()

virtual void clear ( )

virtual

unloads LP.

Reimplemented in SPxSteepPR< R >, SPxAutoPR< R >, and SPxHybridPR< R >.

Definition at line 122 of file spxpricer.h.

References SPxPricer< R >::thesolver.

◆ clone()

virtual SPxPricer* clone ( ) const

pure virtual

clone function for polymorphism

Implemented in SPxHybridPR< R >, SPxSteepPR< R >, SPxWeightPR< R >, SPxParMultPR< R >, SPxDevexPR< R >, SPxAutoPR< R >, SPxDantzigPR< R >, and SPxSteepExPR< R >.

Referenced by SPxPricer< R >::~SPxPricer().

◆ entered4()

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< R >, SPxDevexPR< R >, SPxAutoPR< R >, and SPxHybridPR< R >.

Definition at line 217 of file spxpricer.h.

◆ epsilon()

virtual R epsilon ( ) const

virtual

returns violation bound theeps.

Definition at line 134 of file spxpricer.h.

References SPxPricer< R >::theeps.

◆ getName()

virtual const char* getName ( ) const

virtual

get name of pricer.

Definition at line 108 of file spxpricer.h.

References SPxPricer< R >::m_name.

◆ isConsistent()

virtual bool isConsistent ( ) const

virtual

Reimplemented in SPxSteepPR< R >, SPxWeightPR< R >, SPxDevexPR< R >, and SPxHybridPR< R >.

Definition at line 253 of file spxpricer.h.

References SPxPricer< R >::thesolver.

Referenced by SPxPricer< R >::operator=().

◆ left4()

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< R >, SPxDevexPR< R >, SPxAutoPR< R >, and SPxHybridPR< R >.

Definition at line 189 of file spxpricer.h.

References SPxPricer< R >::selectEnter().

◆ load()

virtual void load ( SPxSolverBase< R > * p_solver )

virtual

loads LP.

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

Reimplemented in SPxSteepPR< R >, SPxWeightPR< R >, SPxParMultPR< R >, SPxDevexPR< R >, SPxAutoPR< R >, and SPxHybridPR< R >.

Definition at line 116 of file spxpricer.h.

References SPxPricer< R >::thesolver.

◆ operator=()

SPxPricer& operator= ( const SPxPricer< R > & rhs )

assignment operator

Definition at line 281 of file spxpricer.h.

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

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

◆ removedCoVec()

virtual void removedCoVec ( int )

virtual

covector i was removed from loaded LP.

Reimplemented in SPxSteepPR< R >, and SPxWeightPR< R >.

Definition at line 243 of file spxpricer.h.

◆ removedCoVecs()

virtual void removedCoVecs ( const int * )

virtual

covectors given by perm have been removed from loaded LP.

Definition at line 246 of file spxpricer.h.

◆ removedVec()

virtual void removedVec ( int )

virtual

vector i was removed from loaded LP.

Reimplemented in SPxSteepPR< R >, and SPxWeightPR< R >.

Definition at line 237 of file spxpricer.h.

◆ removedVecs()

virtual void removedVecs ( const int * )

virtual

vectors given by perm have been removed from loaded LP.

Definition at line 240 of file spxpricer.h.

◆ selectEnter()

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 SPxSolverBase<R>::Pricing type.

Implemented in SPxSteepPR< R >, SPxWeightPR< R >, SPxDevexPR< R >, SPxParMultPR< R >, SPxAutoPR< R >, SPxDantzigPR< R >, and SPxHybridPR< R >.

Referenced by SPxPricer< R >::left4().

◆ selectLeave()

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< R >, SPxWeightPR< R >, SPxDevexPR< R >, SPxParMultPR< R >, SPxAutoPR< R >, SPxDantzigPR< R >, and SPxHybridPR< R >.

Referenced by SPxPricer< R >::setRep().

◆ setEpsilon()

virtual void setEpsilon ( R eps )

virtual

sets violation bound.

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

Reimplemented in SPxAutoPR< R >, and SPxHybridPR< R >.

Definition at line 142 of file spxpricer.h.

◆ setRep()

virtual void setRep ( typename SPxSolverBase< R >::Representation )

virtual

sets basis representation.

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

Reimplemented in SPxSteepPR< R >, SPxWeightPR< R >, SPxDevexPR< R >, SPxAutoPR< R >, and SPxHybridPR< R >.

Definition at line 164 of file spxpricer.h.

References SPxPricer< R >::selectLeave().

◆ setType()

virtual void setType ( typename SPxSolverBase< R >::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< R >, SPxWeightPR< R >, SPxParMultPR< R >, SPxDevexPR< R >, SPxAutoPR< R >, and SPxHybridPR< R >.

Definition at line 153 of file spxpricer.h.

References SPxPricer< R >::thesolver.

◆ solver()

virtual SPxSolverBase<R>* solver ( ) const

virtual

returns loaded SPxSolverBase object.

Definition at line 128 of file spxpricer.h.

References SPxPricer< R >::thesolver.

Referenced by SPxParMultPR< R >::clone().

Member Data Documentation

◆ compare

IdxCompare compare

protected

Definition at line 92 of file spxpricer.h.

◆ m_name

const char* m_name

protected

name of the pricer

Definition at line 55 of file spxpricer.h.

Referenced by SPxPricer< R >::getName(), and SPxPricer< R >::operator=().

◆ theeps

R theeps

protected

violation bound

Definition at line 61 of file spxpricer.h.

Referenced by SPxPricer< R >::epsilon(), and SPxPricer< R >::operator=().

◆ thesolver

SPxSolverBase<R>* thesolver

protected

the solver

Definition at line 59 of file spxpricer.h.

Referenced by SPxPricer< R >::clear(), SPxPricer< R >::isConsistent(), SPxPricer< R >::load(), SPxPricer< R >::operator=(), SPxPricer< R >::setType(), SPxPricer< R >::solver(), and SPxPricer< R >::~SPxPricer().

SoPlex

Classes

Public Types

Public Member Functions

Protected Attributes

Detailed Description

template<class R> class soplex::SPxPricer< R >

Member Enumeration Documentation

◆ ViolationType

Constructor & Destructor Documentation

◆ SPxPricer() [1/2]

◆ SPxPricer() [2/2]

◆ ~SPxPricer()

Member Function Documentation

◆ addedCoVecs()

◆ addedVecs()

◆ clear()

◆ clone()

◆ entered4()

◆ epsilon()

◆ getName()

◆ isConsistent()

◆ left4()

◆ load()

◆ operator=()

◆ removedCoVec()

◆ removedCoVecs()

◆ removedVec()

◆ removedVecs()

◆ selectEnter()

◆ selectLeave()

◆ setEpsilon()

◆ setRep()

◆ setType()

◆ solver()

Member Data Documentation

◆ compare

◆ m_name

◆ theeps

◆ thesolver

template<class R>
class soplex::SPxPricer< R >