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Thread: Rounding Decimal Numbers Question

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    Default Rounding Decimal Numbers Question

    How would I round 14.600000000001 into just 14.6? The user inputs a number(double), then the program will spit the calculation out.


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    Super Moderator pbrockway2's Avatar
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    Default Re: Rounding Decimal Numbers Question

    Typically there two ways of producing a human friendly string from a floating point value like a double: have a look at the DecimalFormat class and the format() method of String. (PrintStream instances like System.out have a printf() method which is simlar to the latter)

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    Super Moderator pbrockway2's Avatar
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    Default Re: Rounding Decimal Numbers Question

    Sorry, I realise I didn't *exactly* address what you asked. Almost always it's a human friendly string that's wanted and not a - necessarily *less* accurate - floating point value. Rounding in this sense is problematic, not least because it's not at all obvious that Java floating point values are even capable of unambiguously representing the matgematical magnitude 14.6 together with it's infinity of trailling zeros.

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    Default Re: Rounding Decimal Numbers Question

    My output is 14.6000000001. How would I change it to only output 14.6?

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    Administrator copeg's Avatar
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    Default Re: Rounding Decimal Numbers Question

    Quote Originally Posted by Nuggets View Post
    My output is 14.6000000001. How would I change it to only output 14.6?
    See http://www.javaprogrammingforums.com...al-places.html

  6. The Following User Says Thank You to copeg For This Useful Post:

    Nuggets (March 19th, 2012)

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    Default Re: Rounding Decimal Numbers Question

    Thank You copeg!!!

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