I am trying to get percentage but the result is error, i have expression as:
Uper=(Upcount/total)*100;
where Uper is float while Upcount and total is integer i am getting the result Uper=0.
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Zsolt Botykai
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Salman Raza
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there is not ant error in code i am just getting "0 " vlaue ?? – Salman Raza Jan 03 '12 at 10:52
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See http://stackoverflow.com/questions/3144610/java-integer-division-how-do-you-produce-a-double – Dime Jan 03 '12 at 10:53
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can u pls mention the values of variables ??? – jaychapani Jan 03 '12 at 10:54
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1If `Upcount` and `total` are both `int` you will receive integer division, probably 0. Better make Uper double and do `(Upcount*100.0)/total`. Naming convention would be **uper** and **upcount**. – Joop Eggen Jan 03 '12 at 10:54
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Did you find an appropriate answer? – Adel Boutros Jan 03 '12 at 13:55
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An int divided by an int will result in an int. That could be 0. Multiply 0 * 100, convert to float, and the result is still 0.0. You need at least one of the operands to be floating point before the division will give a floating point result.
Try:
Uper = ((float)Upcount/(float)total)*100.0;
The extra (float) is me being paranoid that this line might be modified in the future without fully understanding the floating-point requirement. The 100.0 is to be explicit about what you want -- a floating point result.
Perhaps changing Upcount or total to float would make more sense.
sarnold
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1If at least one member of the mathematical operation is a Float/Double then the result will always be a Float/Doube. No need to pe paranoid and add 3 casts when you can do it with 1 cast only – Adel Boutros Jan 03 '12 at 11:17
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There's only two casts. Yes, it's a bit noisy to read but in my experience code changes often over time, sometimes with brute-force search and replace mechanisms, and someone comes along later to fix compile errors without necessarily understanding the _reason_ for code to be written in a certain way. Write whatever makes the most sense for _you_ -- as I've written this code in the manner I think gives it the best chance of surviving maintenance programmers for a decade to come. – sarnold Jan 03 '12 at 11:21
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You are right about everyone writing the way they like but in the problem we have here, it is not relating to a programming language, it is rather a basic concept of Computers because the division differs between integers and floating point values. So the automation part is not required but by the machine itself for computing purposes – Adel Boutros Jan 03 '12 at 13:54
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the division of 2 integers will always result in an integer which is 0 in your case.
To solve this, use the following code:
Uper = ((Double) Upcount) / total * 100
Casting at least 1 member to Double or Float will get the result you want
Adel Boutros
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