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ClpDualRowPivot Class Reference

#include <ClpDualRowPivot.hpp>

Inheritance diagram for ClpDualRowPivot:

ClpDualRowDantzig List of all members.

Public Member Functions

Algorithmic methods
virtual int pivotRow ()=0
 Returns pivot row, -1 if none.

virtual double updateWeights (CoinIndexedVector *input, CoinIndexedVector *spare, CoinIndexedVector *updatedColumn)=0
 Updates weights and returns pivot alpha.

virtual void updatePrimalSolution (CoinIndexedVector *input, double theta, double &changeInObjective)=0
virtual void saveWeights (ClpSimplex *model, int mode)
virtual void checkAccuracy ()
 checks accuracy and may re-initialize (may be empty)

virtual void unrollWeights ()
 Gets rid of last update (may be empty).

virtual void clearArrays ()
 Gets rid of all arrays (may be empty).

virtual bool looksOptimal () const
 Returns true if would not find any row.

Constructors and destructors
 ClpDualRowPivot ()
 Default Constructor.

 ClpDualRowPivot (const ClpDualRowPivot &)
 Copy constructor.

ClpDualRowPivotoperator= (const ClpDualRowPivot &rhs)
 Assignment operator.

virtual ~ClpDualRowPivot ()
 Destructor.

virtual ClpDualRowPivotclone (bool copyData=true) const=0
 Clone.

Other
ClpSimplexmodel ()
 Returns model.

int type ()
 Returns type (above 63 is extra information).


Protected Attributes

Protected member data
ClpSimplexmodel_
 Pointer to model.

int type_
 Type of row pivot algorithm.


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 19 of file ClpDualRowPivot.hpp.


Member Function Documentation

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 , infeasibilities

Definition at line 53 of file ClpDualRowPivot.cpp.

References model_.

Referenced by ClpSimplexDual::statusOfProblemInDual().

00054 {
00055   model_=model;
00056 }

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 ClpDualRowDantzig.

Referenced by ClpSimplexDual::whileIterating().


The documentation for this class was generated from the following files:
Generated on Wed Dec 3 14:37:38 2003 for CLP by doxygen 1.3.5