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From Paul Davis <paul.joseph.da...@gmail.com>
Subject Re: Help on grouping data by date
Date Wed, 09 Dec 2009 20:02:08 GMT
On Wed, Dec 9, 2009 at 2:43 PM, Matteo Caprari <matteo.caprari@gmail.com> wrote:
> Hi Paul.
>
> This is interesting. I assumed that the rereduce may be feeded with
> output from the rereduce itself,
> while you seem to imply that the output of the rereduce is always a
> final value (ie is one row in the view output).
>
> Am I misreading your mail?
>
> Thanks for the pointers.
>

You misread a bit. A rereduce does take multiple values as inputs. The
note about just recalculating the average was that you can do it
server side to avoid it client side. Ie, exactly like you're doing,
but add in the final calculation to avoid it client side. The
reduce.js example has an explicit example of doing this with the
standard deviation where it always calculates a 'partial' standard
deviation.

HTH,
Paul Davis

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