"Newbie" questions - "unique" sorting ?

Bryan belred1 at yahoo.com
Thu Jun 26 03:54:03 CEST 2003


i just did a test comparing:

if key not in mydict:

and

if not mydict.has_key(key):

and the 1st way cameout 28% faster.  (on python 2.3)

bryan

"Erik Max Francis" <max at alcyone.com> wrote in message
news:3EFA2521.94B42B9B at alcyone.com...
> Cousin Stanley wrote:
>
> > I changed one line in the script ....
> >
> >     from .... if this_word not in dict_words.keys()  :
> >
> >     to ...... if not dict_words.has_key( this_word ) :
> ...
> > I failed to consider here
> > that a  NEW  keys list might be created
> > on each pass through a loop ....
>
> Not only does it create a new keys list (D.keys()), but it searches
> linearly through it (x in L)!  Those are two separate O(n) operations,
> whereas D.has_key is effectively O(1).
>
> -- 
>    Erik Max Francis && max at alcyone.com && http://www.alcyone.com/max/
>  __ San Jose, CA, USA && 37 20 N 121 53 W && &tSftDotIotE
> /  \ The multitude of books is making us ignorant.
> \__/  Voltaire






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