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B Is there a way to find the integer representation of a real number?

  1. Oct 11, 2018 #1
    Is there a way to find the integer of a real number? Of course without using the [x] function. What I am looking for here is an algebraic formula.
  2. jcsd
  3. Oct 11, 2018 #2


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    You want an algorithm for a function without allowing the use of functions, right ?

    How about IF statements ? Range of your function ?

    (by the way, in many computer languages a = b does tthe trick if a is an integer and b a real :smile: )
    Last edited by a moderator: Oct 11, 2018
  4. Oct 11, 2018 #3


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    You can get pretty close by starting with arctan(tan(x)). This gives you a sawtooth which you can shift, scale and subtract from f(x)=x. It's just those pesky points where tan x is undefined that get you.

    Will you allow arctan2 as part of an algebraic formula?
  5. Oct 11, 2018 #4

    jim mcnamara

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    To get answers that you want, you will note that the posters so far have asked how you define algebraic. These answers are reasonable. Please provide a solid definition. We cannot leave the thread open, if you continue to have the people who are helping you forced to guess. Thanks.
  6. Oct 12, 2018 #5

    jim mcnamara

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    Staff: Mentor

    Since the OP has come back to the site and ignored the request for question improvement, this thread is closed. Thanks to the two posters who gave it a good try.
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