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Ceiling and floor operators used for min max

  1. Dec 8, 2015 #1
    I remember seeing somewhere people using symbols for ceiling and floor operators together with super/subscripts as substitutes for min and max. Example:
    [tex]\lceil x \rceil ^k[/tex]
    to mean min(x,k).

    Has anyone ever seen this? Where? Thanks!
  2. jcsd
  3. Dec 8, 2015 #2
    I'm sorry, I haven't seen this. But I just wanted to say that this certainly ranks among the top 10 worst notations I've ever seen.
  4. Dec 8, 2015 #3


    Staff: Mentor

    I haven't seen the notation as you used it, to give the minimum of two numbers, but I have seen this:
    ##\lceil x \rceil##, also called the smallest integer function. It is defined as being the smallest integer that is greater than or equal to x. Many programming languages, including C, C++, and others, have a ceiling function, ceil(x), that does this.
    For example, ##\lceil 1.8 \rceil = 2##.

    The counterpart is the floor function, or greatest integer function, denoted ##\lfloor x \rfloor##. C, C++, and others have floor(x). This is defined as the largest integer that is less than or equal to x.
    For example, ##\lfloor 2.35 \rfloor = 2##.

    I agree with micromass that ##\lceil x \rceil^k## is terrible notation.
  5. Dec 8, 2015 #4


    User Avatar
    Science Advisor

    It would be a reasonable notation for denoting the smallest multiple of k greater than or equal to x. That is, the generalization of ceiling to a modulus other than 1.
  6. Dec 9, 2015 #5
    Yes, that's definitely incorrect notation and most people will confuse it as exponents. As someone else stated, the notation that is correct and seen in programming languages is [7.8]=8 or [5.1]=5. These are more standard and less likely to be confused.
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