looking up dictionaries by values

James Stroud jstroud at mbi.ucla.edu
Fri Mar 11 03:49:44 CET 2005


See the thread from earlier today, this list (python-list at python.org).

"newbie: dictionary - howto get key value"

On Thursday 10 March 2005 06:26 pm, Sandman wrote:
> Hi there,
>   I'm still a bit new to Python, and had a question.
> I have a dictionary that looks like:
> PWD = \
>   {
>    "root":     0,
>    "joe":     200,
>    "susan":   201,
> ..
> }
>
>   In other words, the values are unique as well as the keys. I've run
> into a situation where I need to lookup the item by value. So given
> 201, I need to say the key is really susan.
>
>  Is there a way to do this that does not traverse the entire dictionary
> multiple times?
>
> Thanks.

-- 
James Stroud, Ph.D.
UCLA-DOE Institute for Genomics and Proteomics
Box 951570
Los Angeles, CA 90095



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