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ClpDualRowPivot Class Referenceabstract

Dual Row Pivot Abstract Base Class. More...

#include <ClpDualRowPivot.hpp>

+ Inheritance diagram for ClpDualRowPivot:
+ Collaboration diagram for ClpDualRowPivot:

Public Member Functions

Algorithmic methods
virtual int pivotRow ()=0
 Returns pivot row, -1 if none. More...
 
virtual double updateWeights (CoinIndexedVector *input, CoinIndexedVector *spare, CoinIndexedVector *spare2, CoinIndexedVector *updatedColumn)=0
 Updates weights and returns pivot alpha. More...
 
virtual void updatePrimalSolution (CoinIndexedVector *input, double theta, double &changeInObjective)=0
 Updates primal solution (and maybe list of candidates) Uses input vector which it deletes Computes change in objective function Would be faster if we kept basic regions, but on other hand it means everything is always in sync. More...
 
virtual void saveWeights (ClpSimplex *model, int mode)
 Saves any weights round factorization as pivot rows may change Will be empty unless steepest edge (will save model) May also recompute infeasibility stuff 1) before factorization 2) after good factorization (if weights empty may initialize) 3) after something happened but no factorization (e.g. More...
 
virtual void checkAccuracy ()
 checks accuracy and may re-initialize (may be empty) More...
 
virtual void unrollWeights ()
 Gets rid of last update (may be empty) More...
 
virtual void clearArrays ()
 Gets rid of all arrays (may be empty) More...
 
virtual bool looksOptimal () const
 Returns true if would not find any row. More...
 
virtual void maximumPivotsChanged ()
 Called when maximum pivots changes. More...
 
Constructors and destructors
 ClpDualRowPivot ()
 Default Constructor. More...
 
 ClpDualRowPivot (const ClpDualRowPivot &)
 Copy constructor. More...
 
ClpDualRowPivotoperator= (const ClpDualRowPivot &rhs)
 Assignment operator. More...
 
virtual ~ClpDualRowPivot ()
 Destructor. More...
 
virtual ClpDualRowPivotclone (bool copyData=true) const =0
 Clone. More...
 
Other
ClpSimplexmodel ()
 Returns model. More...
 
void setModel (ClpSimplex *newmodel)
 Sets model (normally to NULL) More...
 
int type ()
 Returns type (above 63 is extra information) More...
 

Protected Attributes

Protected member data
ClpSimplexmodel_
 Pointer to model. More...
 
int type_
 Type of row pivot algorithm. More...
 

Detailed Description

Dual Row Pivot Abstract Base Class.

Abstract Base Class for describing an interface to an algorithm to choose row pivot in dual simplex algorithm. For some algorithms e.g. Dantzig choice then some functions may be null.

Definition at line 22 of file ClpDualRowPivot.hpp.

Constructor & Destructor Documentation

ClpDualRowPivot::ClpDualRowPivot ( )

Default Constructor.

ClpDualRowPivot::ClpDualRowPivot ( const ClpDualRowPivot )

Copy constructor.

virtual ClpDualRowPivot::~ClpDualRowPivot ( )
virtual

Destructor.

Member Function Documentation

virtual int ClpDualRowPivot::pivotRow ( )
pure virtual

Returns pivot row, -1 if none.

Implemented in ClpDualRowSteepest, and ClpDualRowDantzig.

virtual double ClpDualRowPivot::updateWeights ( CoinIndexedVector input,
CoinIndexedVector spare,
CoinIndexedVector spare2,
CoinIndexedVector updatedColumn 
)
pure virtual

Updates weights and returns pivot alpha.

Also does FT update

Implemented in ClpDualRowSteepest, and ClpDualRowDantzig.

virtual void ClpDualRowPivot::updatePrimalSolution ( CoinIndexedVector input,
double  theta,
double &  changeInObjective 
)
pure virtual

Updates primal solution (and maybe list of candidates) Uses input vector which it deletes Computes change in objective function Would be faster if we kept basic regions, but on other hand it means everything is always in sync.

Implemented in ClpDualRowSteepest, and ClpDualRowDantzig.

virtual void ClpDualRowPivot::saveWeights ( ClpSimplex model,
int  mode 
)
virtual

Saves any weights round factorization as pivot rows may change Will be empty unless steepest edge (will save model) May also recompute infeasibility stuff 1) before factorization 2) after good factorization (if weights empty may initialize) 3) after something happened but no factorization (e.g.

check for infeasible) 4) as 2 but restore weights from previous snapshot 5) for strong branching - initialize to 1 , infeasibilities 6) scale back 7) for strong branching - initialize full weights , infeasibilities

Reimplemented in ClpDualRowSteepest.

virtual void ClpDualRowPivot::checkAccuracy ( )
virtual

checks accuracy and may re-initialize (may be empty)

virtual void ClpDualRowPivot::unrollWeights ( )
virtual

Gets rid of last update (may be empty)

Reimplemented in ClpDualRowSteepest.

virtual void ClpDualRowPivot::clearArrays ( )
virtual

Gets rid of all arrays (may be empty)

Reimplemented in ClpDualRowSteepest.

virtual bool ClpDualRowPivot::looksOptimal ( ) const
inlinevirtual

Returns true if would not find any row.

Reimplemented in ClpDualRowSteepest.

Definition at line 69 of file ClpDualRowPivot.hpp.

virtual void ClpDualRowPivot::maximumPivotsChanged ( )
inlinevirtual

Called when maximum pivots changes.

Reimplemented in ClpDualRowSteepest.

Definition at line 73 of file ClpDualRowPivot.hpp.

ClpDualRowPivot& ClpDualRowPivot::operator= ( const ClpDualRowPivot rhs)

Assignment operator.

virtual ClpDualRowPivot* ClpDualRowPivot::clone ( bool  copyData = true) const
pure virtual

Clone.

Implemented in ClpDualRowSteepest, and ClpDualRowDantzig.

ClpSimplex* ClpDualRowPivot::model ( )
inline

Returns model.

Definition at line 99 of file ClpDualRowPivot.hpp.

void ClpDualRowPivot::setModel ( ClpSimplex newmodel)
inline

Sets model (normally to NULL)

Definition at line 104 of file ClpDualRowPivot.hpp.

int ClpDualRowPivot::type ( )
inline

Returns type (above 63 is extra information)

Definition at line 109 of file ClpDualRowPivot.hpp.

Member Data Documentation

ClpSimplex* ClpDualRowPivot::model_
protected

Pointer to model.

Definition at line 121 of file ClpDualRowPivot.hpp.

int ClpDualRowPivot::type_
protected

Type of row pivot algorithm.

Definition at line 123 of file ClpDualRowPivot.hpp.


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