Cartesian3D.h

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// @(#)root/mathcore:$Id: 2fd203872f434b1e4e74933903abb3429494ea6f $
// Authors: W. Brown, M. Fischler, L. Moneta    2005
 
/**********************************************************************
 *                                                                    *
 * Copyright (c) 2005 , LCG ROOT MathLib Team                         *
 *                    & FNAL LCG ROOT Mathlib Team                    *
 *                                                                    *
 *                                                                    *
 **********************************************************************/
 
// Header file for class Cartesian3D
//
// Created by: Lorenzo Moneta  at Mon May 30 11:16:56 2005
// Major revamp:  M. Fischler  at Wed Jun  8 2005
//
// Last update: $ID: $
//
#ifndef ROOT_MathX_GenVectorX_Cartesian3D
#define ROOT_MathX_GenVectorX_Cartesian3D 1
 
#include "MathX/GenVectorX/Polar3Dfwd.h"
 
#include "Math/Math.h"
 
#include "MathX/GenVectorX/eta.h"
 
#include "MathX/GenVectorX/MathHeaders.h"
 
#include "MathX/GenVectorX/AccHeaders.h"
 
using namespace ROOT::ROOT_MATH_ARCH;
 
#include <limits>
#include <cmath>
 
namespace ROOT {
 
namespace ROOT_MATH_ARCH {
 
//__________________________________________________________________________________________
/**
    Class describing a 3D cartesian coordinate system
    (x, y, z coordinates)
 
    @ingroup GenVectorX
 
    @see GenVectorX
*/
 
template <class T = double>
class Cartesian3D {
 
public:
   typedef T Scalar;
 
   /**
      Default constructor  with x=y=z=0
   */
   constexpr Cartesian3D() noexcept = default;
 
   /**
      Constructor from x,y,z coordinates
   */
   constexpr Cartesian3D(Scalar xx, Scalar yy, Scalar zz) noexcept : fX(xx), fY(yy), fZ(zz) {}
 
   /**
      Construct from any Vector or coordinate system implementing
      X(), Y() and Z()
   */
   template <class CoordSystem>
   explicit constexpr Cartesian3D(const CoordSystem &v) : fX(v.X()), fY(v.Y()), fZ(v.Z())
   {
   }
 
   /**
      Set internal data based on an array of 3 Scalar numbers
   */
   void SetCoordinates(const Scalar src[])
   {
      fX = src[0];
      fY = src[1];
      fZ = src[2];
   }
 
   /**
      get internal data into an array of 3 Scalar numbers
   */
   void GetCoordinates(Scalar dest[]) const
   {
      dest[0] = fX;
      dest[1] = fY;
      dest[2] = fZ;
   }
 
   /**
      Set internal data based on 3 Scalar numbers
   */
   void SetCoordinates(Scalar xx, Scalar yy, Scalar zz)
   {
      fX = xx;
      fY = yy;
      fZ = zz;
   }
 
   /**
      get internal data into 3 Scalar numbers
   */
   void GetCoordinates(Scalar &xx, Scalar &yy, Scalar &zz) const
   {
      xx = fX;
      yy = fY;
      zz = fZ;
   }
 
   Scalar X() const { return fX; }
   Scalar Y() const { return fY; }
   Scalar Z() const { return fZ; }
   Scalar Mag2() const { return fX * fX + fY * fY + fZ * fZ; }
   Scalar Perp2() const { return fX * fX + fY * fY; }
   Scalar Rho() const { return math_sqrt(Perp2()); }
   Scalar R() const { return math_sqrt(Mag2()); }
   Scalar Theta() const { return math_atan2(Rho(), Z()); }
   Scalar Phi() const { return math_atan2(fY, fX); }
 
   // pseudorapidity
   Scalar Eta() const { return Impl::Eta_FromRhoZ(Rho(), fZ); }
 
   /**
       set the x coordinate value keeping y and z constant
   */
   void SetX(Scalar xx) { fX = xx; }
 
   /**
       set the y coordinate value keeping x and z constant
   */
   void SetY(Scalar yy) { fY = yy; }
 
   /**
       set the z coordinate value keeping x and y constant
   */
   void SetZ(Scalar zz) { fZ = zz; }
 
   /**
       set all values using cartesian coordinates
   */
   void SetXYZ(Scalar xx, Scalar yy, Scalar zz)
   {
      fX = xx;
      fY = yy;
      fZ = zz;
   }
 
   /**
      scale the vector by a scalar quantity a
   */
   void Scale(Scalar a)
   {
      fX *= a;
      fY *= a;
      fZ *= a;
   }
 
   /**
      negate the vector
   */
   void Negate()
   {
      fX = -fX;
      fY = -fY;
      fZ = -fZ;
   }
 
   /**
      Assignment from any class implementing x(),y() and z()
      (can assign from any coordinate system)
   */
   template <class CoordSystem>
   Cartesian3D &operator=(const CoordSystem &v)
   {
      fX = v.x();
      fY = v.y();
      fZ = v.z();
      return *this;
   }
 
   /**
      Exact equality
   */
   bool operator==(const Cartesian3D &rhs) const { return fX == rhs.fX && fY == rhs.fY && fZ == rhs.fZ; }
   bool operator!=(const Cartesian3D &rhs) const { return !(operator==(rhs)); }
 
   // ============= Compatibility section ==================
 
   // The following make this coordinate system look enough like a CLHEP
   // vector that an assignment member template can work with either
   T x() const { return X(); }
   T y() const { return Y(); }
   T z() const { return Z(); }
 
   // ============= Overloads for improved speed ==================
 
   template <class T2>
   explicit Cartesian3D(const Polar3D<T2> &v) : fZ(v.Z())
   {
      const T rho = v.Rho();
      // re-using this instead of calling v.X() and v.Y()
      // is the speed improvement
      fX = rho * math_cos(v.Phi());
      fY = rho * math_sin(v.Phi());
   }
   // Technical note:  This works even though only Polar3Dfwd.h is
   // included (and in fact, including Polar3D.h would cause circularity
   // problems). It works because any program **using** this ctor must itself
   // be including Polar3D.h.
 
   template <class T2>
   Cartesian3D &operator=(const Polar3D<T2> &v)
   {
      const T rho = v.Rho();
      fX = rho * math_cos(v.Phi());
      fY = rho * math_sin(v.Phi());
      fZ = v.Z();
      return *this;
   }
 
#if defined(__MAKECINT__) || defined(G__DICTIONARY)
 
   // ====== Set member functions for coordinates in other systems =======
 
   void SetR(Scalar r);
 
   void SetTheta(Scalar theta);
 
   void SetPhi(Scalar phi);
 
   void SetRho(Scalar rho);
 
   void SetEta(Scalar eta);
 
#endif
 
private:
   T fX = 0; // x coordinate
   T fY = 0; // y coordinate
   T fZ = 0; // z coordinate
};
 
} // end namespace ROOT_MATH_ARCH
 
} // end namespace ROOT
 
#if defined(__MAKECINT__) || defined(G__DICTIONARY)
#if !defined(ROOT_MATH_SYCL) && !defined(ROOT_MATH_CUDA)
// need to put here setter methods to resolve nasty cyclical dependencies
// I need to include other coordinate systems only when Cartesian is already defined
// since they depend on it
#include "MathX/GenVectorX/GenVector_exception.h"
#include "MathX/GenVectorX/CylindricalEta3D.h"
#include "MathX/GenVectorX/Polar3D.h"
 
// ====== Set member functions for coordinates in other systems =======
 
namespace ROOT {
 
namespace ROOT_MATH_ARCH {
 
template <class T>
void Cartesian3D<T>::SetR(Scalar r)
{
   GenVector_exception e("Cartesian3D::SetR() is not supposed to be called");
   throw e;
   Polar3D<Scalar> v(*this);
   v.SetR(r);
   *this = Cartesian3D<Scalar>(v);
}
 
template <class T>
void Cartesian3D<T>::SetTheta(Scalar theta)
{
   GenVector_exception e("Cartesian3D::SetTheta() is not supposed to be called");
   throw e;
   Polar3D<Scalar> v(*this);
   v.SetTheta(theta);
   *this = Cartesian3D<Scalar>(v);
}
 
template <class T>
void Cartesian3D<T>::SetPhi(Scalar phi)
{
   GenVector_exception e("Cartesian3D::SetPhi() is not supposed to be called");
   throw e;
   Polar3D<Scalar> v(*this);
   v.SetPhi(phi);
   *this = Cartesian3D<Scalar>(v);
}
 
template <class T>
void Cartesian3D<T>::SetRho(Scalar rho)
{
   GenVector_exception e("Cartesian3D::SetRho() is not supposed to be called");
   throw e;
   CylindricalEta3D<Scalar> v(*this);
   v.SetRho(rho);
   *this = Cartesian3D<Scalar>(v);
}
 
template <class T>
void Cartesian3D<T>::SetEta(Scalar eta)
{
   GenVector_exception e("Cartesian3D::SetEta() is not supposed to be called");
   throw e;
   CylindricalEta3D<Scalar> v(*this);
   v.SetEta(eta);
   *this = Cartesian3D<Scalar>(v);
}
 
} // end namespace ROOT_MATH_ARCH
 
} // end namespace ROOT
 
#endif
#endif
 
#endif /* ROOT_MathX_GenVectorX_Cartesian3D  */