defaultdict and dict?
hniksic at xemacs.org
Fri Nov 9 12:24:05 CET 2007
Davy <zhushenli at gmail.com> writes:
> In Python 2.5 document, defaultdict is called high performance
> container. From document, we can know defaultdict is subclass of dict.
> So, why defaultdict have higher performance than dict?
I don't think the "high performance" attribute is supposed to mean
that it has higher performanec than dict, only that it is not a
simple-minded hack on top of dict, but code carefully written in C
with performance in mind -- like dict itself.
> That is, when use defaultdict and when use dict? Any suggestions are
Use defaultdict when you need the dict to handle missing keys
automatically, dict in all other cases. If in doubt, simply use dict.
More information about the Python-list