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Thread: Java Math Curiosity

  1. #1
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    Default Java Math Curiosity

    I'm currently learning lava and i have been playing around with some simple tasks.


    Code:
    public class Main {
    	public static void main(String args[]){
     
    		int counter = 0;
    		double number = 0;
     
    		while (counter <= 10){
     
    			number += .2;
    			System.out.println(number);
    			counter++;
     
    		}
     
    	}
    }

    Output:
    0.2
    0.4
    0.6000000000000001
    0.8
    1.0
    1.2
    1.4
    1.5999999999999999
    1.7999999999999998
    1.9999999999999998
    2.1999999999999997

    Why does the output have uneven values?


  2. #2
    Super Moderator Norm's Avatar
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    Default Re: Java Math Curiosity

    Floating point numbers can not be represented exactly in a computer.
    If you don't understand my answer, don't ignore it, ask a question.

  3. #3
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    Default Re: Java Math Curiosity

    What could i use to avoid this?

  4. #4
    Super Moderator Norm's Avatar
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    Default Re: Java Math Curiosity

    That is how floating point variables work.
    If you want to see different values displayed when printing floating point variables, use a formatting class like the DecimalFormat class or the printf() method with formatting Strings.
    If you don't understand my answer, don't ignore it, ask a question.

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