Conversion from int to double

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Views: 293 | Replies: 7

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Join Date: Jun 2008

Location: Pretoria, South Africa

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edman

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Conversion from int to double

Jul 8th, 2008

I am trying to convert the ouput of this recursive function to double, but no matter what I try the output remains integer. Could someone please assist.

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int main()
{
	int x,y;
	cout << "Please enter the low value of the range to add: " << endl;
	cin >> x;
	cout << "Please enter the high value of the range to add: " << endl;
	cin >> y;
	cout << "The sum of the range is: " << static_cast<double>(addRange(x,y)) << endl;
	cin.get();//To keep console window open
	cin.get();//To keep console window open
	return 0;
}

double addRange(int x, int y)
{
	if (x > y)	
		return (0);
	else
		return static_cast<double>(addRange(static_cast<double>(x) + 1,y)) + x;
}

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Join Date: Oct 2006

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niek_e

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Re: Conversion from int to double

Jul 8th, 2008

Why all the horrible casting?
Why not just change the function to take in doubles?

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double addRange(double x, double y)
{

Last edited by niek_e : Jul 8th, 2008 at 10:46 am.

do NOT pm me for help, it makes me angry. You wouldn't like me when I'm angry...

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Join Date: Jun 2008

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edman

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Re: Conversion from int to double

Jul 8th, 2008

This is an assignment question and we were spcifically asked to return a double from this recursive function that passes two int parameters. It is senseless, I know :-)

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Narue

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Re: Conversion from int to double

Jul 8th, 2008

>no matter what I try the output remains integer
If you perform an operation on two integers that wouldn't have any precision even if converted to a double, why would you expect anything but a zero precision? No amount of casting will create something that isn't there.

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Join Date: Apr 2008

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ivailosp

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Re: Conversion from int to double

Jul 8th, 2008

 Help with Code Tags 
 cpp Syntax (Toggle Plain Text) 
#include <iostream>
using namespace std;
double addRange(int x, int y);
int main() {
	int x, y;
	cout << "Please enter the low value of the range to add: " << endl;
	cin >> x;
	cout << "Please enter the high value of the range to add: " << endl;
	cin >> y;
	cout << "The sum of the range is: " << addRange(x, y) << endl;
	cin.get();//To keep console window open
	cin.get();//To keep console window open
	return 0;
}
 
double addRange(int x, int y) {
	if (x > y)
		return (0);
	else
		return (addRange(x + 1, y)) + x;
}
#include <iostream>
using namespace std;
double addRange(int x, int y);
int main() {
	int x, y;
	cout << "Please enter the low value of the range to add: " << endl;
	cin >> x;
	cout << "Please enter the high value of the range to add: " << endl;
	cin >> y;
	cout << "The sum of the range is: " << addRange(x, y) << endl;
	cin.get();//To keep console window open
	cin.get();//To keep console window open
	return 0;
}

double addRange(int x, int y) {
	if (x > y)
		return (0);
	else
		return (addRange(x + 1, y)) + x;
}

lol, works fine...

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Narue

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Re: Conversion from int to double

Jul 8th, 2008

>lol, works fine...
Yes, but I imagine the OP wants the precision to be printed as well. Input of 1 and 5 should print 15.000000 rather than 15, for example. To do that has nothing to do with the type and everything to do with how it's printed:

 Help with Code Tags 
 cplusplus Syntax (Toggle Plain Text) 
cout<<"The sum of the range is: "<< fixed << addRange(x, y) <<endl;
cout<<"The sum of the range is: "<< fixed << addRange(x, y) <<endl;