A.I.M.S algorithms


gmlfunc.h
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33 
34 
35 #ifndef AIMS_ESTIMATION_GMLFUNC_H
36 #define AIMS_ESTIMATION_GMLFUNC_H
37 
38 
40 #include <aims/estimation/m-func.h>
41 #include <aims/math/mathelem.h>
42 
43 
44 //
45 // Geman/McLure M-estimator function
46 //
48 {
49  public:
51  ~GMLFunc() { }
52 
53  float norm( float error ) const;
54  float influence( float error ) const;
55  float weight( float error ) const;
56 };
57 
58 
59 inline
60 float GMLFunc::norm( float error ) const
61 {
62  float e2 = aims::sqr( error );
63  return e2 / ( e2 + _sigma2 );
64 }
65 
66 
67 inline
68 float GMLFunc::influence( float error ) const
69 {
70  return 2.0 * _sigma2 * error / ( aims::sqr( aims::sqr( error ) + _sigma2 ) );
71 }
72 
73 
74 inline
75 float GMLFunc::weight( float error ) const
76 {
77  if ( error )
78  return influence( error ) / error;
79  else
80  return 2.0 / _sigma2;
81 }
82 
83 
84 #endif
float _sigma2
Definition: m-func.h:63
virtual float weight(float) const
Definition: m-func.h:52
GMLFunc()
Definition: gmlfunc.h:50
virtual float norm(float) const
Definition: m-func.h:50
~GMLFunc()
Definition: gmlfunc.h:51
float weight(float error) const
Definition: gmlfunc.h:75
virtual float influence(float) const
Definition: m-func.h:51
float norm(float error) const
Definition: gmlfunc.h:60
float influence(float error) const
Definition: gmlfunc.h:68
#define AIMSALGO_API