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Calculator Vs computer precision

  1. Feb 3, 2013 #1
    Calculator Vs computer....precision

    Im doing a simple research to find out which device is better for calculations

    Valueof π
    On scientific calculator = 3.141592654
    on computer calculator = 3.14159265359

    How do I find percent error?

    And would this difference have any impact on calculations performed in rel life? An example would be nice thanks
  2. jcsd
  3. Feb 3, 2013 #2

    I like Serena

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    Re: Calculator Vs computer....precision

    Welcome to PF, mc2_phy! :smile:

    How about WolframAlpha: http://m.wolframalpha.com/input/?i=pi&x=0&y=0
    Not that you can click on More digits if you are not satisfied with the precision.

    The percentage error is the error divided by the number.
    On your scientific calculator that is ##{3.141592654 - 3.14159265359 \over 3.14159265359} = 4.1 \times 10^{-10}##.

    For real life calculations, the difference won't matter.
    For more exotic calculations, such as in advanced physics, it does matter.
    An example is GPS. For the calculations involved you need more precision than either your scientific or computer calculator gives.
  4. Feb 3, 2013 #3
    Re: Calculator Vs computer....precision

    What do you mean by "computer calculator" ? Computers have much more power than any calculators so in principle you can write better calculation software even on the worst computers today.
    Also there are pi calculating programs out there like y-cruncher with which you can compute million digits of pi for seconds( I think its limited to trillion digits) on the cheapest PC you can buy today.
    In real life scenario so many digits would be absolutely useless.
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