Message-ID: <434E5B44.7080204@brandywine.com>
Date: Thu, 13 Oct 2005 09:04:04 -0400
From: Daryl Richter <daryl@brandywine.com>
Reply-To: daryl@brandywine.com
Organization: Brandywine Asset Management
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To: pgsql-sql@postgresql.org
Subject: Re: SEVEN cross joins?!?!?
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Frank Bax wrote:
> At 09:00 AM 10/12/05, Daryl Richter wrote:
> 
>> Richard Huxton wrote:
>>
>>> Frank Bax wrote:
>>>

[snip]

> 
> Richard, you've summed it up nicely.
> 
> Splitting locations into subsets (like 2,2,3) doesn't work because it is 
> possible that low values in one location can be offset by high values in 
> another location, and still result in an excellent combo.
> 
> The good news is these suggestions got me thinking outside the box.  I 
> think I can program a modified brute-force that bypasses large numbers 
> of combos early.  It might still be too large/slow, so I'd be interested 
> in finding more info about these "smarter algorithms" in option 2.  
> Where do I look?
>

If you're mathematically inclined, I would first look at using
Lagrangian Relexation, it may be appropriate for your problem:

http://www.2112fx.com/lagrange.html

> Greg: my son's the gamer; I'm just trying to help him out.
> 
> 
> ---------------------------(end of broadcast)---------------------------
> TIP 6: explain analyze is your friend


-- 
Daryl Richter
Director of Technology

((         Brandywine Asset Management          )
  ( "Expanding the Science of Global Investing"  )
  (          http://www.brandywine.com           ))