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2    	/*                                                                           */
3    	/*                  This file is part of the class library                   */
4    	/*       SoPlex --- the Sequential object-oriented simPlex.                  */
5    	/*                                                                           */
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7    	/*                                                                           */
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11   	/*                                                                           */
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22   	/*                                                                           */
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24   	
25   	/**@file  spxdantzigpr.h
26   	 * @brief Dantzig pricer.
27   	 */
28   	#ifndef _SPXDEFAULTPR_H_
29   	#define _SPXDEFAULTPR_H_
30   	
31   	#include <assert.h>
32   	
33   	#include "soplex/spxpricer.h"
34   	
35   	namespace soplex
36   	{
37   	
38   	/**@brief   Dantzig pricer.
39   	   @ingroup Algo
40   	
41   	   Class SPxDantzigPR is an implementation class of an SPxPricer implementing
42   	   Dantzig's default pricing strategy, i.e., maximal/minimal reduced cost or
43   	   maximally violated constraint.
44   	
45   	   See SPxPricer for a class documentation.
46   	*/
47   	template <class R>
48   	class SPxDantzigPR : public SPxPricer<R>
49   	{
50   	private:
51   	   int                   selectLeaveSparse();/**< sparse pricing method for leaving Simplex */
52   	
53   	   SPxId
54   	   selectEnterX();                                /**< choose the best entering index among columns and rows but prefer sparsity */
55   	   SPxId                 selectEnterSparseDim(R& best,
56   	         SPxId& id);   /**< sparse pricing method for entering Simplex (slack variables)*/
57   	   SPxId                 selectEnterSparseCoDim(R& best,
58   	         SPxId& id); /**< sparse pricing method for entering Simplex */
59   	   SPxId                 selectEnterDenseDim(R& best,
60   	         SPxId& id);    /**< selectEnter() in dense case (slack variables) */
61   	   SPxId                 selectEnterDenseCoDim(R& best,
62   	         SPxId& id);  /**< selectEnter() in dense case */
63   	public:
64   	
65   	   //-------------------------------------
66   	   /**@name Constructors / destructors */
67   	   ///@{
68   	   /// default constructor
69   	   SPxDantzigPR()
70   	      : SPxPricer<R>("Dantzig")
71   	   {}
72   	   /// copy constructor
73   	   SPxDantzigPR(const SPxDantzigPR& old)
74   	      : SPxPricer<R>(old)
75   	   {}
76   	   /// assignment operator
77   	   SPxDantzigPR& operator=(const SPxDantzigPR& rhs)
78   	   {
79   	      if(this != &rhs)
80   	      {
81   	         SPxPricer<R>::operator=(rhs);
82   	      }
83   	
84   	      return *this;
85   	   }
86   	   /// destructor
87   	   virtual ~SPxDantzigPR()
88   	   {}
89   	   /// clone function for polymorphism
90   	   inline virtual SPxPricer<R>* clone() const
91   	   {
92   	      return new SPxDantzigPR(*this);
93   	   }
94   	   ///@}
95   	
96   	
97   	   //-------------------------------------
98   	   /**@name Select enter/leave */
99   	   ///@{
100  	   ///
101  	   virtual int selectLeave();
102  	   ///
103  	   virtual SPxId selectEnter();
104  	   ///@}
105  	};
106  	} // namespace soplex
107  	
108  	// For general tempalted functions
109  	#include "spxdantzigpr.hpp"
110  	
111  	#endif // _SPXDEFAULTPRR_H_
112