Vectors.h

#ifndef GEAR_Vectors_H
#define GEAR_Vectors_H 1

#include <stdexcept> 

namespace gear {


  template <int N, typename Float_T=double>
  class VectorND_T {
    
  public: 

    VectorND_T() {} ;

    inline Float_T& operator[](unsigned i) {  
      
      if( i > N-1 ) throw std::out_of_range( "VectorND_T::operator[]" ) ;
      
      return _c[i]  ; 
    } 
    inline Float_T operator[](unsigned i) const {  
      
      if( i > N-1 ) throw std::out_of_range( "VectorND_T::operator[]" ) ;
      
      return _c[i]  ; 
    } 
    
  protected:
    
    Float_T _c[N] ; 
    
  }; // class
  

  template <typename Float_T=double>
  struct Vector2D_T : public VectorND_T<2,Float_T> {
    typedef VectorND_T<2,Float_T> Base ;
    Vector2D_T() { 
      Base::_c[0] = 0. ; 
      Base::_c[1] = 0. ; 
    }
    Vector2D_T( Float_T c0, Float_T c1 ) {
      Base::_c[0] = c0 ; 
      Base::_c[1] = c1 ; 
    } 
  } ;
  
  template <typename Float_T=double>
  struct Vector3D_T : public VectorND_T<3,Float_T> {
    typedef VectorND_T<3,Float_T> Base ;
    Vector3D_T() { 
      Base::_c[0] = 0. ; 
      Base::_c[1] = 0. ; 
      Base::_c[2] = 0. ;
    }
    Vector3D_T( Float_T c0, Float_T c1, Float_T c2 ) { 
      Base::_c[0] = c0 ;
      Base::_c[1] = c1 ; 
      Base::_c[2] = c2 ; 
    } 
  } ;
  


  typedef Vector2D_T<double> Vector2D ;
  
  typedef Vector3D_T<double> Vector3D ;
  
  //  gear::Vector3D_T<Float_T>::Vector3D_T()
  
} // namespace gear

#endif /* ifndef GEAR_Vectors_H */

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