Re: Aggregates: Largest Groups
From: David Fetter <david_at_fetter.org>
Date: Mon, 22 Mar 2010 16:12:50 -0500
Message-ID: <uqednXVve-PPQDrWnZ2dnUVZ_oWdnZ2d_at_speakeasy.net>
Date: Mon, 22 Mar 2010 16:12:50 -0500
Message-ID: <uqednXVve-PPQDrWnZ2dnUVZ_oWdnZ2d_at_speakeasy.net>
Gene Wirchenko <genew_at_ocis.net> wrote:
> On Mon, 22 Mar 2010 15:42:09 -0500, david_at_fetter.org (David Fetter)
> wrote:
>
>>Let's say I have a traffic monitoring system. The stream of data
>>coming in records a timestamp and a speed for each vehicle.
>>
>>I'd like to know what all the groups of vehicles larger than X whose
>>with average speed over Y is.
>>
>>Any ideas how to approach this?
> > First, define your terms. What is a group? What does "larger > than X" mean? (Size of vehicle? Number of vehicles in the group?)
Number of vehicles in the group.
Cheers,
David.
-- David Fetter <david_at_fetter.org> http://fetter.org/ Phone: +1 415 235 3778 AIM: dfetter666 Yahoo!: dfetter Skype: davidfetter XMPP: david.fetter_at_gmail.com Just because you do not take an interest in politics doesn't mean politics won't take an interest in you. Pericles, statesman (430 BCE)Received on Mon Mar 22 2010 - 22:12:50 CET