Thread: STL - Maps

  1. #1
    Registered User
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    Sep 2003
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    STL - Maps

    Is there a way to estimate the amount of time it will take to use a map, given the number of elements it contains and the operation being done to the map (e.g. addition, subtraction, division, etc.)? If I am running an application at a high frequency, is it a good idea to use maps?

  2. #2
    Hardware Engineer
    Join Date
    Sep 2001
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    1,398

    Lightbulb Look-up "Big-O Notation"

    (That's big-oh, not big zero)

    This gives you the relative time that an operation takes, depending on the number of elements. That is - if you double the number of elements, does the time operation change at all? Does it double? Does it quadruple?

    You still have to test the program to see how long the operations will take. Then Big-O will help you estimate the time with larger data sets.

    [EDIT]:
    Here's a link with some info about Big-O and the STL. I didn't thoroughly read it... but it shows what the Big-O numbers mean:
    1) Constant
    2) Logarithmic
    3) Linear
    4) Amortized
    Last edited by DougDbug; 09-03-2003 at 05:22 PM.

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