Simple Arithmetic Problem

[Jerri Loh]

hi there, wanna check if i am coding this wrongly:

 int sumOfVotes = 23
 int howlong = 94
double SimPercent = ((sumOfVotes / howlong) *100);  

Shouldn't the answer, SimPercent, be 24.4 How come I am getting 0.0

Tks!

[Hunter McMillen]

integer division truncates everything after the decimal point, so if you had an expression that was supposed to result in 0.244 (i.e. 23/43) you would only get the 0.
You should make sumOfVotes and howLong ints, or cast the expression to an int.

Hunter

[Jerri Loh]

thanks hunter,

but yr suggestion doesn't work out.

But i got it solved.
Kramed from Daniweb:

The problem is you are doing integer division, which will truncate rather than round as you expect. In Java, 5/2 = 2 and 2/5 = 0 . To fix this problem, you need to make one of the operands in the division a floating point type (either float or double). Again, in Java, (float)5/2 = 2.5 and 2/(double)5 = 0.5 .

[Hunter McMillen]

actually both of my suggestions work:

  int sumOfVotes = 23;
         int howlong = 94;
         double SimPercent = (((double)sumOfVotes / (double)howlong) *100);  
			System.out.println(SimPercent);  

  double sumOfVotes = 23;
         double howlong = 94;
         double SimPercent = ((sumOfVotes / howlong) *100);  
			System.out.println(SimPercent);  

both print: 24.46808510638298

Hunter

[Matthew Brown]

Your suggestion would have worked if you hadn't accidentally written "int" instead of "double" .

[Hunter McMillen]

Haha, I read my own post 5 times and didn't notice that; thank you for pointing it out.


Hunter