trouble with overloaded operator
Hey I am having some trouble getting operator/ to overload to a midpoint formula for a Point class. And yes, I have to make operator/ find the midpoint it was part of the assignment.
Anyway I came up with this:
Code:
// Overloaded operator/ to return the midpoint
// between two Point objects, however it does not
// work and only returns garbage.
Point & Point::operator/(const Point & p) const
{
return Point(((x + p.x) / 2.0), ((y + p.y) / 2.0));
}
here is the header file if you want to look at that too:
Code:
#ifndef POINT_CLASS_HEADER_INCLUDED
#define POINT_CLASS_HEADER_INCLUDED
#include <iostream>
// A 2D point class
class Point
{
double x, // x coordinate of point
y; // y coordinate of point
public:
Point(void);
Point(double new_x, double new_y);
Point(const Point & p);
void Output(void); // output this point
void Input(void); // input this point
double distance(Point other); // distance between this point and other
double get_x(void) { return x; }
double get_y(void) { return y; }
void set_x(double new_x);
void set_y(double new_y);
Point flip_x(void);
Point flip_y(void);
Point shift_x(double move_by);
Point shift_y(double move_by);
Point & operator=(const Point & p);
Point & operator/(const Point & p) const;
double operator-(const Point & p) const;
bool operator==(const Point & p) const;
bool operator!=(const Point & p) const;
double operator[](const char axis) const;
double & operator[](const char axis);
friend std::istream & operator>>(std::istream & in, Point & p);
friend std::ostream & operator<<(std::ostream & out, const Point & p);
};
#endif
Anyway I was wondering if that is an invalid operator overload and if it is how can a hack it together to get it to work? Any ideas?
Re: trouble with overloaded operator
Quote:
Originally posted by kkurz
Hey I am having some trouble getting operator/ to overload to a midpoint formula for a Point class. And yes, I have to make operator/ find the midpoint it was part of the assignment.
Anyway I came up with this:
Code:
// Overloaded operator/ to return the midpoint
// between two Point objects, however it does not
// work and only returns garbage.
Point & Point::operator/(const Point & p) const
{
return Point(((x + p.x) / 2.0), ((y + p.y) / 2.0));
}
You are returning a reference to a new Point object created on the stack inside the operator/ function. When the function ends, all objects created inside it are destroyed, including the one that you returned a reference to. The reference you returned is then pointing at diddly poo. In this case I'd say return a Point and not a Point reference.
