Speed of string += string

Marcus Alanen marcus at infa.abo.fi
Mon Apr 14 12:40:38 CEST 2003


On Sat, 12 Apr 2003 20:14:51 -0400, Roy Smith <roy at panix.com> wrote:
>One of the very few things I like about C++ over Python is that the STL 
>is very careful to document the complexity of the various operations.  
>AFAICT, no such documentation exists for Python.

Indeed, that was the first thing I wondered about when I started
learning Python.

>As another example, I can guess that Python dictionaries work like STL 
>maps on the inside, but that would be just a guess.  Is inserting an 
>element logN?  Is keys() linear?  Is del on an element logN?  Is 
>has_key() logN?  Those would be my guesses.  But they're just guesses.

Others answered this very thoroughly, I'd just like to emphasize the
linearity of keys() --- most often you can manage with .iterkeys() or
.itervalues() just fine, and it's a lot faster.

-- 
Marcus Alanen
maalanen at abo.fi




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