* Peter Corlett ([EMAIL PROTECTED]) wrote:
> In article <[EMAIL PROTECTED]> you write:
> > ok, but it gets more interesting as take into account moores law that
> > reduces the effectiveness of optmisation by halving the improvement of the
> > optimization every year [...]
> 
> This depends. If you're just doing an optimisation that changes one O(N)
> algorithm for another, then you're probably better off with the most clear
> version and wait for Moore's Law to help. Cycle-pinching optimisation
> doesn't really gain much anyway.
> 
> [Mind you, I suspect that index and the equivalent regexen may have
> different O() scores. Discuss.]
> 
> However, the problem is with programmers that don't really understand
> algorithms and implement something the "obvious" way, e.g. O(N^2) instead of
> O(NlogN) then this is not going to help when you attempt to scale your
> website or whatever to a million users instead of a test set of five.
> 

the best way to do this, if you see something is N^2 is to figure out
how you could do it with a sort and hey presto it usually can be turned
into NlogN+N .. NlogN


-- 
Greg McCarroll                          http://www.mccarroll.uklinux.net

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