#ifndef _MFormulary_
#define _MFormulary_

#include <iostream.h>
#include "TMath.h"

class MFormulary : public TMath
{
 public:
    
    MFormulary(); // Constructor
    virtual ~MFormulary(); // Destructor
						       
    // constants

    Double_t C() { return 299792458.; }                                                   // velocity of light
    
    
    // mathematics

    Double_t Mt(const Double_t *m, const Double_t *pt);                                   // transverse mass
    Double_t Pt(const Double_t *p);                                                       // transverse momentum
    Double_t Y(const Double_t *p, const Char_t t);                                        // rapidity
    Double_t Y(const Double_t *eta, const Double_t *pt, const Double_t *m);               // rapidity
    Double_t Eta(const Double_t *p, const Char_t t);                                      // pseudorapidity
    Double_t Eta(const Double_t *y, const Double_t *mt, const Double_t *m);               // pseudorapidity
    Double_t Energy(const Double_t p[4]);                                                 // energy
    Double_t Gamma(const Double_t *v);                                                    // gamma factor
    Double_t RelativisticSum(const Double_t *v1, const Double_t *v2);                     // sum of two velocities
    Double_t InvDist_squared(const Double_t x1[4], const Double_t x2[4]);                 // square of the space-time distance
    Double_t InvDist(const Double_t x1[4], const Double_t x2[4]);                         // space-time distance
    Double_t RelativisticScalarProd(const Double_t x1[4], const Double_t x2[4]);          // scalar product in Minkowski metrik												 
        void Lorentz(const Double_t *v, Double_t p[4]);                                   // Lorentz transform of four momentum (1D)
        void LorentzBoost(const Double_t x[4], Double_t x_prime[4], const Double_t v[3]); // Lorentz transform (4D)
    
    Double_t S(const Double_t p_a[4], const Double_t p_b[4]);				  // Mandelstam variable s
    Double_t T(const Double_t p_a[4], const Double_t p_c[4]);		                  // Mandelstam variable t
    Double_t U(const Double_t p_a[4], const Double_t p_d[4]);		                  // Mandelstam variable u 

    
    // experimental

    Double_t Sigma_tot_pp(Double_t *p);                                                   // p+p total cross section
    Double_t Sigma_el_pp(Double_t *p);                                                    // p+p elastic cross section
    Double_t N_charged(Double_t *s);                                                      // p+p charged multiplicity

    
    // true mathematics

        void Pq(const Double_t *p, const Double_t *q, Double_t x[2]);                     // x(y=0) values of a parabola
    Double_t Angle(const Double_t *x1, const Double_t *x2, Int_t dim = 3);                // angle between to vectors
    Double_t Dist_squared(const Double_t *p1, const Double_t *p2, Int_t dim);             // squared distance of two points in space
    Double_t Dist(const Double_t *p1,  const Double_t *p2, Int_t dim);                    // distance of two points in space
        void VectorProd(const Double_t *a, const Double_t *b, Double_t *c);               // vector product (3D)
    Double_t ScalarProd(const Double_t *a, const Double_t *b, Int_t dim);                 // scalar product of two verctors
    Double_t Square(const Double_t *p, Int_t dim);                                        // squared length of a vector
    void Sum(const Double_t *p1, const Double_t *p2, Double_t *P, Int_t n);               // sum of two vectors
    void Diff(const Double_t *p1, const Double_t *p2, Double_t *P, Int_t n);              // difference of two vectors
    Double_t Abs(const Double_t *p, Int_t dim);                                           // length of a vector

    ClassDef(MFormulary,0)  // Mathematical and physical formulary
};    

#endif