creating/modifying sparse files on linux
benji at benjiyork.com
Thu Aug 18 14:21:42 CEST 2005
Terry Reedy wrote:
> megastring = 1000000*'a' # t < 1 sec on my machine
>>(other than keep appending to a string until it reaches 1MB len)?
> You mean like (unexecuted)
> s = ''
> for i in xrange(1000000): s += 'a' #?
> This will allocate, copy, and deallocate 1000000 successively longer
> temporary strings and is a noticeable O(n**2) operation.
Not exactly. CPython 2.4 added an optimization of "+=" for strings.
The for loop above takes about 1 second do execute on my machine. You
are correct in that it will take *much* longer on 2.3.
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