include/Geant4/Gamma.hh

0001 //
0002 // ********************************************************************
0003 // * License and Disclaimer                                           *
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0024 // ********************************************************************
0025 //
0026 //
0027 //
0028 //
0029 //
0030 //---------------------------------------------------------------
0031 //  GEANT 4 class header file
0032 //
0033 //  Gamma
0034 //
0035 //  Class description:
0036 //
0037 //  Gamma function.
0038
0039 //---------------------------------------------------------------
0040 #ifndef MYGAMMA_H
0041 #define MYGAMMA_H
0042
0043 #include <cmath>
0044
0045 class MyGamma
0046 {
0047   public:
0048     MyGamma();
0049     ~MyGamma();
0050
0051     double Gamma(double z);
0052     double Gamma(double a, double x);
0053
0054   private:
0055     double GamCf(double a, double x);
0056     double GamSer(double a, double x);
0057
0058     // Abs
0059     static short Abs(short d) { return (d > 0) ? d : -d; }
0060     static int Abs(int d) { return (d > 0) ? d : -d; }
0061     static long   Abs(long d)   { return (d > 0) ? d : -d; }
0062     static float  Abs(float d)  { return (d > 0) ? d : -d; }
0063     static double Abs(double d) { return (d > 0) ? d : -d; }
0064     static double LnGamma(double z);
0065     static double Log(double x) { return std::log(x); }
0066     static double Exp(double x) { return std::exp(x); }
0067 };
0068
0069 #endif