Thread: efficiency

  1. #1
    Registered User
    Join Date
    May 2011


    i know this is no c++ question, can any one tel me:
    in efficiency class is log2^n the same and log3^n or logx^n, because we can change base right?

    thanks in advance .

  2. #2
    Master Apprentice phantomotap's Avatar
    Join Date
    Jan 2008

    Are you talking about "BigO"?

    If so, yes, because constant factors are abstracted away because they don't affect growth potential.

    (Unless you are taking about trying to make a O(logN(N)) algorithm look like something it probably isn't.)


  3. #3
    (?<!re)tired Mario F.'s Avatar
    Join Date
    May 2006
    ... and why it's not even usually spelled as O(logn^n), but simply O(log n)
    Last edited by Mario F.; 06-14-2011 at 03:15 PM.
    Originally Posted by brewbuck:
    Reimplementing a large system in another language to get a 25% performance boost is nonsense. It would be cheaper to just get a computer which is 25% faster.

  4. #4
    Registered User
    Join Date
    Apr 2006

    So if you have a bunch of functions that have a log term of any base, you can convert them to functions of a log term of your favorite base, with a constant product. Constant products are ignored in O(N) notation, so it doesn't matter what base is used; they are all comparable, as long as it is greater than 1.
    It is too clear and so it is hard to see.
    A dunce once searched for fire with a lighted lantern.
    Had he known what fire was,
    He could have cooked his rice much sooner.

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