In mathematics, computer science, and related fields, big O notation describes the limiting behavior of a function when the argument tends towards a particular value or infinity, usually in terms of simpler functions. Big O notation allows its users to simplify functions in order to concentrate on their growth rates: different functions with the same growth rate may be represented using the same O notation.

Although developed as a part of pure mathematics, this notation is now frequently also used in computational complexity theory to describe an algorithm's usage of computational resources: the worst case or average case running time or memory usage of an algorithm is often expressed as a function of the length of its input using big O notation. This allows algorithm designers to predict the behavior of their algorithms and to determine which of multiple algorithms to use, in a way that is independent of computer architecture or clock rate. Big O notation is also used in many other fields to provide similar estimates.

Big O notation is also called Big Oh notation, Landau notation, Bachmann–Landau notation, and asymptotic notation. A description of a function in terms of big O notation usually only provides an upper bound on the growth rate of the function; associated with big O notation are several related notations, using the symbols o, Ω, ω, and Θ, to describe other kinds of bounds on asymptotic growth rates.

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Mon Oct 12 15:25:42 2009

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f n = O g n means there are positive constants c and k such that 0 f n cg n for all n k The values of c and k must be fixed for the function f and must not depend on n Also known as O See also n

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where O f n is Big O notation Just take the exponential on both sides and choose any positive integer m say 1 We get the formula with an unknown term ey

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asserts that there exist constants C and N such that

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Must List Live!: Should the 'Big Brother' cliques be broken up? - Entertainment Weekly
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Must List Live!: Should the ' Big Brother' cliques be broken up?

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oh my god! Make her go away! Courtney's smug celebration of her own ignorance is just excruciating. (Did you figure that since BB brought back an irritant, ...
UK Big Brother Housemates Learn Michael Jackson Died - Anglophenia
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UK Big Brother Housemates Learn Michael Jackson Died

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(Mirror) Oh , and BBC World News America was nominated for three News & Documentary Emmy Awards: Outstanding Coverage of a Breaking News Story in a Regularly ...

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NSE Sez: OK Big O , (I've always wanted to call someone that), Good comments, but you can't rely on manufacturing rb's the way that the Broncs have in the ...



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Thu Nov 12 22:03:38 2009

What's an easy way to understand Big-O notation?
Q. I don't get this Big-O notation stuff (I was never good with math). Is there like a quick rule of thumb to understand how to choose an algorithm based on just its Big-O notation? For example, what would be considered slow and fast in Big-O notation?
Asked by retroman - Sun Sep 24 16:08:00 2006 - - 1 Answers - 0 Comments

A. This is not entirely mathematically correct, but here goes: O(1) < O(x) < O(xlogx) < O(x^2) < ... < O (x^n) That reads algorithm of speed Big O of 1 is always faster than algorithm of speed Big O of x and algorithm of speed Big O of x is always faster than algorithm of speed Big O of xlogx and so on. The variable x stands for input size; that could be size of array, depth of a tree, population of a tree, length of a string, whatever, but it is some quantity of size not the value of input itself, a quick way of understanding O() is the extra steps that an algorithm has to go through for a growth in input size: if no extra - it is O(1) speed if growth and extra steps are proportionate - O(x) if growth:extra step ratio is xlogx - it is O(x [cont.]
Answered by Andy T - Sun Sep 24 16:24:06 2006

What are the Big O notation forms for these?
Q. 5* + n^2 + n^3/2 28*n + 2995 + 37*log(n) 12*log(n) + 5*n + 2*log(log(n))
Asked by Jim - Wed May 6 20:57:49 2009 - - 1 Answers - 0 Comments
What is the time complexity (Big-O notation) of a Binomial Queue? of a Btree?
Q. What is the time complexity (Big-O notation) of a Binomial Queue? of a Btree?
Asked by Rwar - Wed Nov 7 03:49:52 2007 - - 1 Answers - 0 Comments

A. time complexity is exponential
Answered by timo - Wed Nov 7 03:55:13 2007

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Plain English Explanation of Big O Notation ~ C for Coding
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William Shields

hu, 09 Jul 2009 14:48:00 GM

I recently read A Beginners' Guide to . Big O Notation. and while I appreciate such efforts I don't think it went far enough. I'm a huge fan of plain English explanations to, well, anything. Just look at the formal definition of . Big O. . ...

In My Dreams I Can Talk: Oh Bother! Big , Ballooning Blisters!
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In My Dreams I Can Talk: Oh Bother! Big , Ballooning Blisters!

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hu, 27 Aug 2009 13:26:00 GM

Oh. Bother! . Big. , Ballooning Blisters! Hi All! First of all, thank you for the supportive comments I got on my fractious post. I know this will pass . . . . eventually! Well, I made it through another night of class. ...

The Bluegrass Blog Rhonda and The Big O : bluegrass music news
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ue, 11 Aug 2009 23:07:03 GM

A central clearinghouse for bluegrass news and comment, targeted at both industry professionals and folks who would enjoy following what's going on in bluegrass music all over the world.

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