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Java gives wrong answer to calculation

I am trying to do some calculations in Java but for some reason a simple calculation in 1 or 2 lines of code gives me the wrong answer, on the other hand if I do it in 3 steps it works flawlessly.

I know it's not too bad to take a couple more steps, but why use additional text when it can be shortened?

Can anyone give me a pointer if my math is wrong?

this is 1 line of code

percent1 = (((totaloutput1Int - Total1Int) / totaloutput1Int) * 100);

also = (((2232 - 1590) / 2232) * 100)

and this is a multi-step code that works.

percent1step1 = (totaloutput1Int - Total1Int);

percent1step2 = ((percent1step1 / totaloutput1Int)* 100);

percent1Tv.setText(String.valueOf(percent1step2));
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3 answers


Change totaloutput1Int

and Total1Int

from int

to double

and everything will work fine.



In the first method, int / int results in rounding the value. This leads to a different result.

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You need to convert some of your variables to double to get an accurate answer. int

/ int

going to give you int

Take a look at this question



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Since this is labeled Android, I am assuming you are using Android Studio. One of its great features is the lining (also available in most modern IDEs).

Take this:

float percent1step1 = (totaloutput1Int - Total1Int);

float percent1step2 = ((percent1step1 / totaloutput1Int)* 100);

If you right click percent1step1

and select "refactor-> inline" android studio do like this:

float percent1step2 = ((((float)(totaloutput1Int - Total1Int)) / totaloutput1Int)* 100);

Thus, it shows you how to succeed internally, without a few lines. In this case, the result is converted int

from subtraction to float

.

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