ITK  5.0.0
Insight Segmentation and Registration Toolkit
itkCacheableScalarFunction.h
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18 #ifndef itkCacheableScalarFunction_h
19 #define itkCacheableScalarFunction_h
20 
21 #include "itkArray.h"
22 #include "itkIntTypes.h"
23 #include "ITKBiasCorrectionExport.h"
24 
25 namespace itk
26 {
59 class ITKBiasCorrection_EXPORT CacheableScalarFunction
60 {
61 public:
63  CacheableScalarFunction();
64 
66  virtual ~CacheableScalarFunction();
67 
69  using MeasureType = double;
70  using MeasureArrayType = Array< MeasureType >;
71 
74  SizeValueType GetNumberOfSamples() { return m_NumberOfSamples; }
75 
77  bool IsCacheAvailable() { return m_CacheAvailable; }
78 
80  double GetCacheUpperBound() { return m_CacheUpperBound; }
81 
83  double GetCacheLowerBound() { return m_CacheLowerBound; }
84 
88  virtual MeasureType Evaluate(MeasureType x);
89 
91  double GetInterval()
92  { return m_TableInc; }
93 
99  inline MeasureType GetCachedValue(MeasureType x)
100  {
101  if ( x > m_CacheUpperBound || x < m_CacheLowerBound )
102  {
103  throw ExceptionObject(__FILE__, __LINE__);
104  }
105  // access table
106  auto index = (int)( ( x - m_CacheLowerBound ) / m_TableInc );
107  return m_CacheTable[index];
108  }
110 
111 protected:
114  void CreateCache(double lowerBound, double upperBound, SizeValueType sampleSize);
115 
116 private:
119  SizeValueType m_NumberOfSamples{0};
120 
122  MeasureArrayType m_CacheTable;
123 
125  double m_CacheUpperBound{0.0};
126 
128  double m_CacheLowerBound{0.0};
129 
131  double m_TableInc{0.0};
132 
unsigned long SizeValueType
Definition: itkIntTypes.h:83