Divide problem

Question

Hello,

I was very surprised when I found out my code wasn't working so I created a console application to see where the problem lies and I've got even more surprised when I saw the code below returns 0

    static void Main(string[] args)
    {
        float test = 140 / 1058;
        Console.WriteLine(test);
        Console.ReadLine();
    }

I'm trying to get the result in % and put it in a progress(meaning (140 / 1058) * 100) bar on my application,the second value(1058) is actually ulong type in my application,but that doesn't seem to be the problem.

The question is - where the problem is?

Answer 1

You are using integer arithmetic and then converting the result to a float. Use floating-point arithmetic instead:

float test = 140f / 1058f;

Answer 2

The problem is that you are dividing integers and not floats. Only the result is a float. Change the code to be the following

float test = 140f / 1058f;

EDIT

John mentioned that there is a variable of type ulong. If that's the case then just use a cast opeartion

ulong value = GetTheValue();
float test = 140f / ((float)value);

Note, there is a possible loss of precision here since you're going from ulong to float.

Answer 3

This will work the way you expect ...

float test = (float)140 / (float)1058;

By the way, your code works fine for me (prints a 0.1323251 to the console).

Answer 4

The division being performed is integer division. Replace

float test = 140 / 1058;

with

float test = 140f / 1058;

to force floating-point division.

In general, if you have

int x;
int y;

and want to perform floating-point division then you must cast either x or y to a float as in

float f = ((float) x) / y;