A range of options between O(N) and O(N2) makes perfect sense to me. As long as you're not trying to mentally apply Perl's range operator that is. :)

It simply means you've got a choice between, for example: O(N) memory with a huge constant, O(N log N) with a modest constant, or O(N2) with a small constant. Which one you should use depends on the size of N.

When you bring in different independent costs, you could also be considering O(N)cpu and O(N log N) memory, vs O(N log N) cpu and O(N) memory. If you care to think of it this way, there is a multidimensional continuum of efficiencies between O(N) and O(N2) to consider.


BTW, I don't know of anybody who bothers to be technical enough to use "Omega" instead of just saying Big-Oh. Except you I suppose.

In practice, I've found it to always be a "Big-Crossed-Fingers" aka "Best Guess at Omega But Not Worth Strictly Proving; Nobody Wants The Cost To Make It Rigorous."

Few people would know what you're talking about if you said Big-Omega, instead of Big-Oh. Big-Oh gets used as a generic term whenever there are non-mathies around (which is always unless you're still a math student). Bit of a self-sustaining "problem" but as far as I can tell, nobody really cares.

In reply to Re^2: Gay Dating; or, Thrifty Set Intersections with an Accumulator by SuicideJunkie
in thread Gay Dating; or, Thrifty Set Intersections with an Accumulator by Xiong

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