| 1 | #ifndef ALIMATH_H |
| 2 | #define ALIMATH_H |
| 3 | /* Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. * |
| 4 | * See cxx source for full Copyright notice */ |
| 5 | |
| 6 | // $Id$ |
| 7 | |
| 8 | #include <math.h> |
| 9 | |
| 10 | #include "TObject.h" |
| 11 | |
| 12 | class AliMath : public TObject |
| 13 | { |
| 14 | public: |
| 15 | AliMath(); // Default constructor |
| 16 | virtual ~AliMath(); // Destructor |
| 17 | AliMath(const AliMath& m); // Copy constructor |
| 18 | Double_t Gamma(Double_t z) const; // Standard gamma function Gamma(z) |
| 19 | Double_t Gamma(Double_t a,Double_t x) const; // Incomplete gamma function P(a,x) |
| 20 | Double_t LnGamma(Double_t z) const; // Compute ln[Gamma(z)] |
| 21 | Double_t Erf(Double_t x) const; // Error function erf(x) |
| 22 | Double_t Erfc(Double_t x) const; // Complementary error function erfc(x) |
| 23 | Double_t Prob(Double_t chi2,Int_t ndf,Int_t mode=1) const; // Compute Chi-squared probability |
| 24 | Double_t BesselI(Int_t n,Double_t x) const; // Compute integer order mod. Bessel function I_n(x) |
| 25 | Double_t BesselK(Int_t n,Double_t x) const; // Compute integer order mod. Bessel function K_n(x) |
| 26 | |
| 27 | protected: |
| 28 | Double_t GamSer(Double_t a,Double_t x) const; // Compute P(a,x) via serial representation |
| 29 | Double_t GamCf(Double_t a,Double_t x) const; // Compute P(a,x) via continued fractions |
| 30 | Double_t BesselI0(Double_t x) const; // Compute modified Bessel function I_0(x) |
| 31 | Double_t BesselK0(Double_t x) const; // Compute modified Bessel function K_0(x) |
| 32 | Double_t BesselI1(Double_t x) const; // Compute modified Bessel function I_1(x) |
| 33 | Double_t BesselK1(Double_t x) const; // Compute modified Bessel function K_1(x) |
| 34 | |
| 35 | ClassDef(AliMath,3) // Various mathematical tools for physics analysis. |
| 36 | |
| 37 | }; |
| 38 | #endif |