On Jan 3, 2008 11:55 PM, Jack Andrews <[EMAIL PROTECTED]> wrote:
> > You mean like J's /. adverb?
>
> looks interesting... i can kind of see how this could do moving
> averages but can't see how you could apply it to a table like:
> ----+-----
> day | price
> ----+------
> 0   | 1.00
> 1   | 1.20
> 2   | 1.15
> 3   | 1.25
> 4   | 2.90
> 5   | 2.70
> 6   | 2.75

I would use the dyad of verbs formed with \ for moving averages:
   avg=:+/ % #
   3 avg\ 1 1.2 1.15 1.25 2.9 2.7 2.75
1.11667 1.2 1.76667 2.28333 2.78333

And, I had originally meant the dyad \. (which basically works somewhat
like group by, except of course that you can use an arbitrary aggregation
verb).

Anyways... perhaps ^: would be interesting for you to consider.
   3 avg\^:1: 1 1.2 1.15 1.25 2.9 2.7 2.75
1.11667 1.2 1.76667 2.28333 2.78333
   3 avg\^:2: 1 1.2 1.15 1.25 2.9 2.7 2.75
1.36111 1.75 2.27778
   3 avg\^:3: 1 1.2 1.15 1.25 2.9 2.7 2.75
1.7963

-- 
Raul
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