# Difference between two numbers

### Question

• Hi ,

In c# I want to find the integer value of e.g. -5, how do I do this?

For example 10-5 = 5 but 5-10 = -5, I just want to know what the difference is between the two numbers.

Thanks

harry

Thursday, May 24, 2007 4:37 PM

• Math.Abs(i)
Thursday, May 24, 2007 4:52 PM
• I think Math.Abs is what you are looking for.  Here is a quick example ...

static void Main(string[] args)

{

Console.WriteLine(string.Format("Math.Abs(-5): {0}", Math.Abs(-5)));

Console.WriteLine(string.Format("Math.Abs(10 - 5): {0}", Math.Abs(10 - 5)));

Console.WriteLine(string.Format("Math.Abs(5 - 10): {0}", Math.Abs(5 - 10)));

}

Thursday, May 24, 2007 4:54 PM

### All replies

• Math.Abs(i)
Thursday, May 24, 2007 4:52 PM
• I think Math.Abs is what you are looking for.  Here is a quick example ...

static void Main(string[] args)

{

Console.WriteLine(string.Format("Math.Abs(-5): {0}", Math.Abs(-5)));

Console.WriteLine(string.Format("Math.Abs(10 - 5): {0}", Math.Abs(10 - 5)));

Console.WriteLine(string.Format("Math.Abs(5 - 10): {0}", Math.Abs(5 - 10)));

}

Thursday, May 24, 2007 4:54 PM
• -5 and 5 (any which way you come about them) have a sign difference. Math.Abs has nothing to do with why those two numbers are different (except to show you that they are both 5 away from 0)

in memory (binary, showing only 8-bits):
5 = 0000 0101
-5 = 1111 1011
At least in common negative number system.
5 != -5
but
Math.Abs(5) == Math.Abs(-5)

in terms of finding if a variable is "-5"

if ( i == -5 )
// i is -5

Also remember addition is commutative (can be performed either A+B or B+A) but subtraction is not ( A-B is not the same as B-A )

edit: spelling fix
Thursday, May 24, 2007 7:40 PM
• In mathematics, the difference between two numbers is the subtraction of the two numbers.  The difference between 5 and -5 is 0.

Maybe you can explain differently if that's not what you want.

Thursday, May 24, 2007 11:49 PM
• The previous posts regarding mathematical difference are, of course, correct, but I think the OP was inferring that he was just looking to find a way to return a  positive integer, regardless of the mathematical difference.

Sorry to be pedantic, but the difference between 5 and -5 is 10. (Diff between -5 and 5  is -10)

Friday, May 25, 2007 2:15 AM
•  IsshouFuuraibou wrote:
 Also remember addition is communicative (can be performed either A+B or B+A) but subtraction is not ( A-B is not the same as B-A )

Hi, i think you meant to say addition is commutative not communicative
Friday, May 25, 2007 8:15 AM
• That's not pedantic.
Friday, May 25, 2007 9:13 AM
• Yes, not pedantic: correct.  5 - -5 is 10, not zero.
Friday, May 25, 2007 12:50 PM
•

You are right..you always add the opposite. So 5- -5=10 is equal to 5+ +5=10
Tuesday, April 29, 2008 11:00 PM