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From: dpb <none@non.net>
Newsgroups: comp.soft-sys.matlab
Subject: Re: Summarizing yearly/monthly data in time series
Date: Wed, 28 Oct 2009 19:20:13 -0500
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Oleg Komarov wrote:
> dpb <none@non.net> wrote in message <hcam0p$q32$1@news.eternal-september.org>...
>> Oleg Komarov wrote:
>> ...
>>> Data ranges loose on precision.
>> ...
>> Certainly not at level of days since they're integer values...
>>
>> --
> 
> i used "loose on precision" improperly.
> What i meant is, defining fixed ranges (lets say of 30 days) would
> possibly lead sometimes to group into the same month, one or two days of
> another month.
> suppose i start on the 31 jan, setting 30 days as my range to get montlhy stats.
> 31 jan + 30 would yield 1 or 2 march!

Well, that's not how you would set the intervals, obviously.  One would 
specify the start/end dates and compute the datevalues for those as 
well.  This leaves one w/ a totally generic interface where the user can 
request any range within the database with no changes in algorithm.

--