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SoPlex

Sequential object-oriented simPlex

spxdantzigpr.h
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1 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
2 /* */
3 /* This file is part of the class library */
4 /* SoPlex --- the Sequential object-oriented simPlex. */
5 /* */
6 /* Copyright (C) 1996-2015 Konrad-Zuse-Zentrum */
7 /* fuer Informationstechnik Berlin */
8 /* */
9 /* SoPlex is distributed under the terms of the ZIB Academic Licence. */
10 /* */
11 /* You should have received a copy of the ZIB Academic License */
12 /* along with SoPlex; see the file COPYING. If not email to soplex@zib.de. */
13 /* */
14 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
15 
16 /**@file spxdantzigpr.h
17  * @brief Dantzig pricer.
18  */
19 #ifndef _SPXDEFAULTPR_H_
20 #define _SPXDEFAULTPR_H_
21 
22 #include <assert.h>
23 
24 #include "spxpricer.h"
25 
26 namespace soplex
27 {
28 
29 /**@brief Dantzig pricer.
30  @ingroup Algo
31 
32  Class SPxDantzigPR is an implementation class of an SPxPricer implementing
33  Dantzig's default pricing strategy, i.e., maximal/minimal reduced cost or
34  maximally violated constraint.
35 
36  See SPxPricer for a class documentation.
37 */
38 class SPxDantzigPR : public SPxPricer
39 {
40 private:
41  int selectLeaveSparse();/**< sparse pricing method for leaving Simplex */
42 
43  SPxId selectEnterX(); /**< choose the best entering index among columns and rows but prefer sparsity */
44  SPxId selectEnterSparseDim(Real& best,SPxId& id); /**< sparse pricing method for entering Simplex (slack variables)*/
45  SPxId selectEnterSparseCoDim(Real& best, SPxId& id); /**< sparse pricing method for entering Simplex */
46  SPxId selectEnterDenseDim(Real& best, SPxId& id); /**< selectEnter() in dense case (slack variables) */
47  SPxId selectEnterDenseCoDim(Real& best,SPxId& id); /**< selectEnter() in dense case */
48 public:
49 
50  //-------------------------------------
51  /**@name Constructors / destructors */
52  //@{
53  /// default constructor
55  : SPxPricer("Dantzig")
56  {}
57  /// copy constructor
58  SPxDantzigPR(const SPxDantzigPR& old )
59  : SPxPricer(old)
60  {}
61  /// assignment operator
63  {
64  if(this != &rhs)
65  {
67  }
68 
69  return *this;
70  }
71  /// destructor
72  virtual ~SPxDantzigPR()
73  {}
74  /// clone function for polymorphism
75  inline virtual SPxPricer* clone() const
76  {
77  return new SPxDantzigPR(*this);
78  }
79  //@}
80 
81 
82  //-------------------------------------
83  /**@name Select enter/leave */
84  //@{
85  ///
86  virtual int selectLeave();
87  ///
88  virtual SPxId selectEnter();
89  //@}
90 };
91 } // namespace soplex
92 #endif // _SPXDEFAULTPRR_H_