complex calculator

[rafay_07]

hi i just have made add function yet for complex calculator but its not working
in this function i just want to add real in real part and complex in complex part but compilor says
error C2065: 'o1' : undeclared identifier
error C2228: left of '.real' must have class/struct/union
error C2228: left of '.complx' must have class/struct/union
i think i am missing something kindly guide me here is my code

# include <iostream>
# include <conio.h>
# include <windows.h>
using namespace std;
class complex
{
private:
	double real;
	double complx;
public:
	complex ()
	{
	
	}// defualt constructor
	complex (double r1,double r2) 
	{
		real=r1;
		complx=r2;
	
	}//end constructor 2

	void add (complex o)
	{
		
		real=o.real+o1.real;
		complx=o.complx+o1.complx;
		
	
	}//end function
	


};//end class
int main ()
{
	const complex o(2,4),o1(4,6);
	complex o3;
	o3.add (o1);
	getch ();
	

}//end main

thanks

[whiteflags]

complex is a standard type you know. I wouldn't redefine it as "complex" if I were you, even though it's technically OK in this instance.

OK, aside from that, if you call add like this

o3.add (o1);

Then that means you can add o1, which becomes o in the function, and the member data within the class. You need another parameter if you wanted to do something differently.

[rafay_07]

i have also used

public:
         void add (complex o,complex o1)
	{
		complex temp;
		real=o.real+o1.real;
		complx=o.complx+o1.complx;

		
	
	}//end function
int main ()
{
   const complex o(2,4),o1(4,6);
	complex o3;
	o3.add (o,o1);
}

it works but my requirement is to pass only one object as an argument that is i have failed to do so

[whiteflags]

If you know how return values work you could always add together the object and the argument.

[rafay_07]

now i have modified this code like this

class complex
{
private:
	double real;
	double complx;
public:
	complex ()
	{
	real=0;
	complx=0;
	}// defualt constructor
	complex (double r1,double r2) 
	{
		real=r1;
		complx=r2;
	
	}//end constructor 2

complex add (complex o1)
	{
		complex temp;
		temp.real=o1.real+real;
		temp.complx=o1.complx+complx;
		temp.disp ();
		return (temp);

	}//end function
void disp ()
{
	cout<<real<<"+"<<complx<<"i";

}//end function
	


};//end class
int main ()
{
	 complex o(2,4),o1(4,6);
	complex o3;
	o3=o.add (o1);
	getch ();
	

}//end main

now can i have better than that if i want to extend my code for subtraction, multiplication and division
kindly guide me if i want
when any operator function is called it displays the result like i have done in above code but i want to use one function to display all results of addition multiplication subtraction and division
can i do this without using separate display functions for addition subtraction ,division and multiplication?

[Finchie_88]

Isn't the problem with your original add function that you are attempting to access private class members from outside the class (in this case, from another instance of the same class definition).

    void add (complex o)
    {
        
        real=o.real+o1.real;
        complx=o.complx+o1.complx;
        
    
    }//end function

If you made them public members or alternatively used Getter/Setter methods to access them solve your problems?

[rafay_07]

actually i am also not of this opinion but my requirement is this
kindly give some example may b its closer to my requirement

[iMalc]

it works but my requirement is to pass only one object as an argument that is i have failed to do so

Sure. What two things are you adding then?

IMHO, whiteflags had it right that you'll be wanting to add to the current object. I.e as per +=

[rafay_07]

@ iMalc
the thing u r talking about is it same as in my last posted code?

[whiteflags]

@Finchie:

Isn't the problem with your original add function that you are attempting to access private class members from outside the class (in this case, from another instance of the same class definition).

That's not the problem, and that's not an answer. The problem was that if you called this -- the older version of rafay's code --

	void add (complex o)
	{
		
		real=o.real+o1.real;
		complx=o.complx+o1.complx;
		
	
	}//end function

The problem is that o1 is undefined in the function, and the only ways to define it would be to make a new object called o1 (probably not what was wanted since you'd be adding the same thing all the time) or passing in an object called o1. The latter possibility was eschewed by the requirements.

@rafay:

the thing u r talking about is it same as in my last posted code?

No, he was responding to an earlier post of yours where you talked about requirements on add's argument list. He thinks that I was correct when I suggested adding the argument to the object, and the object would be the answer; or you could define it -- as you did later -- so that the object and argument are added and the result is returned as a new object. It's not clear which is correct and both could work, it (possibly) depends on the assignment. I have no way of knowing.

can i do this without using separate display functions for addition subtraction ,division and multiplication?

Is that really a requirement? It's hard.

The real problem with doing that is unless one of the operands contains information pertaining to the operation, you will need to add an argument. Don't do it if you can avoid it.

If you eschewed functions and overloaded operators for complex, you could then write a function with one argument to do that, but the problem itself is not solved by one function.

[rafay_07]

@ whiteflags
no this is not the requirement i was just trying to shorten my code
i m clear about u said but for me another problem exists if i want to define a multiplication function
in similar way like passing an object as arguments and manipulate multiplication i m trying "this" pointer to do this but compiler says "illegal use of this expression" may b i m defining it in a silly way
yet i have read about "this" pointer is
for input "cin>>(*this).real"
for output "cout<<(*this).real"
but this does not work for me in the multiplication function

[rafay_07]

if i define a multiplication function in this way

{
public:
          complex multiply (complex o)
{
           ?

}
}
int main ()
{
          o3=o.multiply (o1);
}

in place of question mark what should be the definition of this function i m not posting my code for this function defintion because i think it looks silly

[rafay_07]

i m using this rule for multiplication
if one complex number is (x+iy) and other complex number is (a+ib) then
(x+iy)(a+ib)=(ax-by)+(bx+ay)i

[whiteflags]

>> i m clear about u said but for me another problem exists if i want to define a multiplication function
OK, there is probably a way that you could write this that always works no matter what complex numbers you're doing arithmetic on.

>> in similar way like passing an object as arguments and manipulate multiplication i m trying "this" pointer to do this but compiler says "illegal use of this expression" may b i m defining it in a silly way
I'd say you're doing it in a silly way, yeah. Just read into the appropriate variable types for the real and imaginary parts. Then you would take those variables and make a new complex number out of them. Or you could write an input function for complex numbers, and then add. If you go with the latter then the next part will be important.

>> yet i have read about "this" pointer is
for input "cin>>(*this).real"
for output "cout<<(*this).real"
but this does not work for me in the multiplication function
OK well, why? Your compiler gives you a specific error doesn't it?

In any case, the expression (*this).real and real could be the same. You would only write *this if you were resolving an ambiguity. (*this).real refers to the class member real not the local variable, real.

[rafay_07]

did u mean this

void multiply (complex o1)
{
		double x,y;
		x=real* o1.real-complx * o1.real;
		y=real * o1.complx+complx * o1.real;
		cout <<x<<"+"<<y<<endl;
}