Geant4  10.03
G4SimpleIntegration.hh
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27 // $Id: G4SimpleIntegration.hh 69546 2013-05-08 09:50:34Z gcosmo $
28 //
29 // Class description:
30 //
31 // Class for realisation of simple numerical methodes for integration of
32 // functions with signature: double f(double). The methods based mainly on
33 // algorithms given in the book :
34 // An introduction to NUMERICAL METHODS IN C++,
35 // B.H. Flowers, Claredon Press, Oxford, 1995.
36 //
37 // --------------------------- Member data ----------------------------
38 //
39 // fFunction - pointer to the function to be integrated
40 // fTolerance - accuracy of integration in Adaptive Gauss method
41 // fMaxDepth = 100 - constant maximum iteration depth for
42 // Adaptive Gauss method
43 //
44 // --------------------------- Methods --------------------------------
45 //
46 // Trapezoidal, MidPoint, Gauss and Simpson(double a,double b,int n)
47 // - integrate function pointed by fFunction from a to b by n iterations,
48 // i.e. with Step (b-a)/n according to the correspondent method.
49 //
50 // AdaptGausIntegration(double a, double b)
51 // - integrate function from a to be with accuracy <= fTolerance
52 
53 // ----------------------------- History ------------------------------
54 //
55 // 26.03.97 V.Grichine ( Vladimir.Grichine@cern.ch )
56 
57 #ifndef G4SIMPLEINTEGRATION_HH
58 #define G4SIMPLEINTEGRATION_HH
59 
60 #include "G4Types.hh"
61 
62 typedef G4double (*function)(G4double) ;
63 
65 {
66  public:
67 
68  explicit G4SimpleIntegration( function pFunction ) ;
69 
70  G4SimpleIntegration( function pFunction,
71  G4double pTolerance ) ;
72 
74 
75  // Simple integration methods
76 
77  G4double Trapezoidal(G4double xInitial,
78  G4double xFinal,
79  G4int iterationNumber ) ;
80 
81  G4double MidPoint(G4double xInitial,
82  G4double xFinal,
83  G4int iterationNumber ) ;
84 
85  G4double Gauss(G4double xInitial,
86  G4double xFinal,
87  G4int iterationNumber ) ;
88 
89  G4double Simpson(G4double xInitial,
90  G4double xFinal,
91  G4int iterationNumber ) ;
92 
93  // Adaptive Gauss integration with accuracy ~ fTolerance
94 
96  G4double xFinal ) ;
97 
98  protected:
99 
100  G4double Gauss( G4double xInitial,
101  G4double xFinal ) ;
102 
103  void AdaptGauss( G4double xInitial,
104  G4double xFinal,
105  G4double& sum,
106  G4int& depth ) ;
107  private:
108 
111  // Private copy constructor and assignment operator.
112 
113  private:
114 
115  function fFunction ;
117  const G4int fMaxDepth ;
118 };
119 
120 #endif
G4double MidPoint(G4double xInitial, G4double xFinal, G4int iterationNumber)
G4SimpleIntegration & operator=(const G4SimpleIntegration &)
G4SimpleIntegration(function pFunction)
G4double Gauss(G4double xInitial, G4double xFinal, G4int iterationNumber)
G4double AdaptGaussIntegration(G4double xInitial, G4double xFinal)
int G4int
Definition: G4Types.hh:78
void AdaptGauss(G4double xInitial, G4double xFinal, G4double &sum, G4int &depth)
G4double Simpson(G4double xInitial, G4double xFinal, G4int iterationNumber)
G4double Trapezoidal(G4double xInitial, G4double xFinal, G4int iterationNumber)
double G4double
Definition: G4Types.hh:76