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24   	
25   	/**@file  spxgeometsc.h
26   	 * @brief LP geometric mean scaling.
27   	 */
28   	#ifndef _SPXGEOMETSC_H_
29   	#define _SPXGEOMETSC_H_
30   	
31   	#include <assert.h>
32   	
33   	#include "soplex/spxdefines.h"
34   	#include "soplex/spxscaler.h"
35   	
36   	namespace soplex
37   	{
38   	/**@brief Geometric mean row/column scaling.
39   	   @ingroup Algo
40   	
41   	   This SPxScaler implementation performs geometric mean scaling of the
42   	   LPs rows and columns.
43   	*/
44   	template <class R>
45   	class SPxGeometSC : public SPxScaler<R>
46   	{
47   	protected:
48   	
49   	   //-------------------------------------
50   	   /**@name Data */
51   	   ///@{
52   	   const bool postequilibration;  ///< equilibrate after geometric scaling?
53   	   const int  m_maxIterations;    ///< maximum number of scaling iterations.
54   	   const R m_minImprovement;   ///< improvement necessary to carry on. (Bixby said Fourer said in MP 23, 274 ff. that 0.9 is a good value)
55   	   const R m_goodEnoughRatio;  ///< no scaling needed if ratio is less than this.
56   	   ///@}
57   	
58   	public:
59   	
60   	   //-------------------------------------
61   	   /**@name Construction / destruction */
62   	   ///@{
63   	   /// default constructor (this scaler makes no use of inherited members m_colFirst and m_doBoth)
64   	   explicit SPxGeometSC(bool equilibrate = false, int maxIters = 8, R minImpr = 0.85,
65   	                        R goodEnough = 1e3);
66   	   /// copy constructor
67   	   SPxGeometSC(const SPxGeometSC& old);
68   	   /// assignment operator
69   	   SPxGeometSC& operator=(const SPxGeometSC&);
70   	   /// destructor
71   	   virtual ~SPxGeometSC()
72   	   {}
73   	   /// clone function for polymorphism
74   	   inline virtual SPxScaler<R>* clone() const override
75   	   {
76   	      return new SPxGeometSC(*this);
77   	   }
78   	   ///@}
79   	
80   	   //-------------------------------------
81   	   /**@name Scaling */
82   	   ///@{
83   	   /// Scale the loaded SPxLPBase<R>.
84   	   virtual void scale(SPxLPBase<R>& lp, bool persistent = true) override;
85   	   ///@}
86   	
87   	};
88   	} // namespace soplex
89   	
90   	#include "spxgeometsc.hpp"
91   	
92   	#endif // _SPXGEOMETSC_H_
93