Adding a ranking based on two fields

noydb jenn.duerr at gmail.com
Wed Sep 7 21:33:03 CEST 2011


On Aug 25, 4:53 pm, Chris Rebert <c... at rebertia.com> wrote:
> On Thu, Aug 25, 2011 at 1:38 PM, noydb <jenn.du... at gmail.com> wrote:
> > Hello All,
>
> > Looking for some advice/ideas on how to implement arankingto a
> > 'scores' field I have.  So this scores field has values ranging from
> > 1.00-4.  There is also a count field.  I want to add a rank field such
> > that all the records have a uniqueranking, 1 through the number of
> > records (thousands).  The rank isbasedon the score first, the count
> > second.  So, a record with a score of 4 and a count of 385 is ranked
> > higher than a record with a score of 4 and a count of 213 AND higher
> > than record with a score of 3.25 with a count of 4640.
>
> > My thought was to add the unique score values to a list and loop thru
> > the list... sort records with score=listItem, addranking... not quite
> > sure how to do this!
>
> things = getListOfYourThings()
> things.sort(reverse=True, key=lambda item: (item.score, item.count))
> for i, thing in enumerate(things):
>     thing.rank = i + 1
>
> Cheers,
> Chris
> --http://rebertia.com

Thanks for this!

Someone passed this along, too - helpful
http://wiki.python.org/moin/HowTo/Sorting



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