From: Daryl Richter <daryl@brandywine.com>
To: pgsql-sql@postgresql.org
Subject: Re: SEVEN cross joins?!?!?
Date: Thu, 13 Oct 2005 09:04:04 -0400
Message-ID: <434E5B44.7080204@brandywine.com> (raw)
In-Reply-To: <5.2.1.1.0.20051012211223.00a34dd0@pop6.sympatico.ca>
References: <434CE6B8.5060106@archonet.com>
<5.2.1.1.0.20051011071510.0364d850@pop6.sympatico.ca>
<5.2.1.1.0.20051011071510.0364d850@pop6.sympatico.ca>
<5.2.1.1.0.20051011145705.00a31440@pop6.sympatico.ca>
<434CE6B8.5060106@archonet.com>
<5.2.1.1.0.20051012211223.00a34dd0@pop6.sympatico.ca>
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 ))
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To: pgsql-sql@postgresql.org
Cc: daryl@brandywine.com
Subject: Re: SEVEN cross joins?!?!?
In-Reply-To: <434E5B44.7080204@brandywine.com>
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