TwoVector.h

// Class TwoVector
//
// Author: Benno List
// Last update: $Date: 2009/05/22 12:12:07 $
//          by: $Author: blist $
// 
// Description: class for 2-vectors
//               

#ifndef __TWOVECTOR_H
#define __TWOVECTOR_H

#include <iostream>
#include <cmath>

class TwoVector {
  public:
    inline TwoVector();
    inline TwoVector(double x_, double y_);
    // automatically generated copy constructor and assignment is fine
    
    inline double getX()     const;
    inline double getY()     const;
    
    inline double getMag2()    const;
    inline double getMag()   const;
    
    inline double getPhi()   const;
    
    inline double getComponent (int i) const;
    
    inline TwoVector& setValues(double x_, double y_);

    inline TwoVector& operator+= (const TwoVector& rhs);
    inline TwoVector& operator-= (const TwoVector& rhs);
    inline TwoVector& operator*= (double rhs);
    
  private:
    double x, y;
};

TwoVector::TwoVector()
: x(0), y(0)
{}

TwoVector::TwoVector(double x_, double y_)
: x(x_), y(y_)
{}
    
double TwoVector::getX()  const { return x; }
double TwoVector::getY()  const { return y; }

double TwoVector::getMag2() const { return x*x + y*y; }
double TwoVector::getMag()const { return std::sqrt(getMag2()); }

double TwoVector::getPhi()   const { return std::atan2(y, x); }

double TwoVector::getComponent(int i) const { 
  switch (i) {
    case 0: return getX();
    case 1: return getY();
  }
  return NAN; // not-a-number, defined in cmath
}

TwoVector& TwoVector::setValues(double x_, double y_) {
  x = x_;
  y = y_;
  return *this;
}


TwoVector& TwoVector::operator+= (const TwoVector& rhs) {
  x += rhs.x;
  y += rhs.y;
  return *this;
}

TwoVector& TwoVector::operator-= (const TwoVector& rhs) {
  x -= rhs.x;
  y -= rhs.y;
  return *this;
}

TwoVector& TwoVector::operator*= (double rhs) {
  x *= rhs;
  y *= rhs;
  return *this;
}

inline TwoVector operator+ (const TwoVector& lhs, const TwoVector& rhs) {
  return TwoVector (lhs.getX()+rhs.getX(), lhs.getY()+rhs.getY());
}

inline TwoVector operator- (const TwoVector& lhs, const TwoVector& rhs) {
  return TwoVector (lhs.getX()-rhs.getX(), lhs.getY()-rhs.getY());
}

inline TwoVector operator- (const TwoVector& rhs) {
  return TwoVector (-rhs.getX(), -rhs.getY());
}

inline double operator* (const TwoVector& lhs, const TwoVector& rhs) {
  return lhs.getX()*rhs.getX() + lhs.getY()*rhs.getY();
}

inline TwoVector operator* (double lhs, const TwoVector& rhs) {
  return TwoVector (lhs*rhs.getX(), lhs*rhs.getY());
}
    
inline std::ostream& operator<< (std::ostream& out, const TwoVector& v) {
  out << "(" << v.getX() << ", " << v.getY() << ")";
  return out;
}



#endif /* #ifndef __TWOVECTOR_H */