On Sun, 2006-10-29 at 01:32 +0200, Jochem Maas wrote:
> Robert Cummings wrote:
> > On Fri, 2006-10-27 at 13:51 +0200, Jochem Maas wrote:
> >>>>>> range(1, 31)
> >>>>> Memory waster ;)
> >>>> any idea as to what the damage is as compared to the classic for loop?
> >>> Given that a variable probably costs X and that any variable cane be
> >>> stored as Y in an array, and an array would cost Z where the Z = X * Y _
> >>> 1 (Y element + 1 for the array container itself).
> >>>
> >>> Then the range format would cost 31 + 1 (the array itself + 31 entries)
> >>> whereas the for loop would cost 1 + 1 (cost to store i + cost to store
> >>> endpoint comparison. Thus the damage is about 15*. Given general
> >>> computer science consideration, this is a constant and thus practically
> >>> neglible.
> >>>
> >>> Cheers
> >>> Rob (ps. the above may be completely incoherent since I'm completely
> >>> drunk atm after celebrating two friends birthdays tonight).
> >> not a bad explainantion then ;-) it's only the last bit I didn't quite follow :-)
> >
> > *heheh* It makes sense to me, though my head still hurts from last
> > night :)
> >
> > Which part exactly did you not quite follow?
>
> this bit:
>
> Given general computer science consideration, this is a constant and thus practically
> neglible.
In computer science it's common to profile an algorithm using "Big Oh"
notation. In "Big Oh" notation you have:
O( Cn ) = O( n )
Where C is a constant multiplier.
Cheers,
Rob.
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