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4    	/*       SoPlex --- the Sequential object-oriented simPlex.                  */
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24   	
25   	/**@file  spxleastsqsc.h
26   	 * @brief LP least squares scaling.
27   	 */
28   	#ifndef _SPXLEASTSQSC_H_
29   	#define _SPXLEASTSQSC_H_
30   	
31   	#include <assert.h>
32   	#include "soplex/spxsolver.h"
33   	#include "soplex/spxscaler.h"
34   	#include "soplex/spxlp.h"
35   	
36   	
37   	namespace soplex
38   	{
39   	
40   	/**@brief Least squares scaling.
41   	   @ingroup Algo
42   	
43   	   This SPxScaler implementation performs least squares scaling as suggested by Curtis and Reid in:
44   	   On the Automatic Scaling of Matrices for Gaussian Elimination (1972).
45   	*/
46   	template <class R>
47   	class SPxLeastSqSC : public SPxScaler<R>
48   	{
49   	public:
50   	   //-------------------------------------
51   	   /**@name Construction / destruction */
52   	   ///@{
53   	   /// default constructor (this scaler makes no use of inherited member m_colFirst)
54   	   explicit SPxLeastSqSC();
55   	   /// copy constructor
56   	   SPxLeastSqSC(const SPxLeastSqSC& old);
57   	   /// assignment operator
58   	   SPxLeastSqSC& operator=(const SPxLeastSqSC&);
59   	   /// destructor
60   	   virtual ~SPxLeastSqSC()
61   	   {}
62   	   /// clone function for polymorphism
63   	   inline virtual SPxScaler<R>* clone() const override
64   	   {
65   	      return new SPxLeastSqSC(*this);
66   	   }
67   	   ///@}
68   	
69   	   //-------------------------------------
70   	   /**@name Access / modification */
71   	   ///@{
72   	   /// set Real param (conjugate gradient accuracy)
73   	   virtual void setRealParam(R param, const char* name) override;
74   	   /// set int param (maximal conjugate gradient rounds)
75   	   virtual void setIntParam(int param, const char* name) override;
76   	   ///@}
77   	
78   	   //-------------------------------------
79   	   /**@name Scaling */
80   	   ///@{
81   	   /// Scale the loaded SPxLP.
82   	   virtual void scale(SPxLPBase<R>& lp, bool persistent = true) override;
83   	
84   	
85   	private:
86   	   R acrcydivisor = R(1000.0);
87   	   int maxrounds = 20;
88   	
89   	};
90   	} // namespace soplex
91   	
92   	// For the general templated files
93   	#include "spxleastsqsc.hpp"
94   	
95   	#endif // _SPXLEASTSQSC_H_
96   	
97