Solved

Help with output operator

Posted on 2003-10-29
6
163 Views
Last Modified: 2010-04-02
I am trying to take the following header and implementation files and changed them so that an output operator, <<, can be used. The code Point P(14.3, 4.2);
                       cout<<P;
should produce an utput of (14.3, 4.2). What modifications would be necessary to make this happen?
here is my code so far:

header:
#ifndef POINT_H
#define POINT_H
#include <iostream>
#include <conio>

using namespace std;

class Point
{
public:
Point (); //constructor
Point (double, double); //constructor

double GetX () const;
double GetY () const;

private:
double x;
double y;
};
#endif

and the implementation file:
#pragma hdrstop
#include "point.h"
Point::Point ()
{
     x=0;
     y=0;
}

Point::Point ( double InputX, double InputY)
{
x=InputX;
y=InputY;
}

double Point::GetX () const
{
      return x;
}

double Point::GetY () const
{
     return y;
}

please help me out on this
0
Comment
Question by:jba6511
  • 3
6 Comments
 
LVL 86

Accepted Solution

by:
jkr earned 250 total points
ID: 9645613
You'll need a global 'operator<<()', as you cannot add that functionality to 'cout', e.g.

ostream& operator << ( ostream& r, Point& l) {

  r << "(" << l.GetX() << ", " << l.GetY() << ")";

  return r;
}

As the above only uses public members of 'Point', you won't even need to make it a 'friend'.
0
 

Author Comment

by:jba6511
ID: 9645942
what would need to be done if i was to make it a friend then?
0
 
LVL 86

Expert Comment

by:jkr
ID: 9645962
>>what would need to be done if i was to make it a friend then?

You'd use

class Point
{
public:

friend ostream& operator << ( ostream& r, Point& l);

//...
};

in your class definition - but, this is not even necessary...

0
 
LVL 86

Expert Comment

by:jkr
ID: 9671377
Do you have any further problems with this one?
0
 
LVL 9

Expert Comment

by:tinchos
ID: 10546303
No comment has been added lately, so it's time to clean up this question.
I will leave the following recommendation for this question in the Cleanup topic area:

Accept: jkr {http:#9645613}

Please leave any comments here within the next four days.
PLEASE DO NOT ACCEPT THIS COMMENT AS AN ANSWER!

Tinchos
EE Cleanup Volunteer
0

Featured Post

Free Tool: Site Down Detector

Helpful to verify reports of your own downtime, or to double check a downed website you are trying to access.

One of a set of tools we are providing to everyone as a way of saying thank you for being a part of the community.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
SetCurrentDirectory path limit 7 131
show out valin of json for debugging in visaul c++ 1 41
DCT of  2D array using fftw in c++ 9 72
C++ Code Issue 4 26
When writing generic code, using template meta-programming techniques, it is sometimes useful to know if a type is convertible to another type. A good example of when this might be is if you are writing diagnostic instrumentation for code to generat…
Many modern programming languages support the concept of a property -- a class member that combines characteristics of both a data member and a method.  These are sometimes called "smart fields" because you can add logic that is applied automaticall…
The goal of the video will be to teach the user the difference and consequence of passing data by value vs passing data by reference in C++. An example of passing data by value as well as an example of passing data by reference will be be given. Bot…
The viewer will learn additional member functions of the vector class. Specifically, the capacity and swap member functions will be introduced.

820 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question