lucene-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Yonik Seeley <yo...@lucidimagination.com>
Subject Re: [SPATIAL] Best Fit Calculation
Date Wed, 14 Apr 2010 16:24:53 GMT
On Wed, Apr 14, 2010 at 12:12 PM, Chris Male <gento0nz@gmail.com> wrote:
> On Wed, Apr 14, 2010 at 6:07 PM, Grant Ingersoll <gsingers@apache.org>
>> On Apr 14, 2010, at 11:06 AM, Chris Male wrote:
>> > For those doing just Cartesian Tier filtering it seems like the new
>> > approach is a win, but for those doing distance calculations on those
>> > documents passing the filter, it seems to come at a cost.
>>
>> Currently, this is only used for filtering.  AIUI, Tiers aren't really
>> that useful for distance calculations, are they?  After all, all you have is
>> a box id and you'd have to reverse out the calc of that to be able to calc a
>> distance, no?  Perhaps I'm missing something.
>>
>
> How Spatial Lucene currently works (or at least one of the ways it was
> designed to work), is using a 2 step filtering process.  Step 1 is the
> Cartesian Tier filtering.  The resulting set of Documents is then passed on
> through to Step 2 which then calculates the distance from each Document to
> the search centre.

IMO, being able to just do a tier or bounding box  filter is also
useful (step 1).
One example is if someone is going to sort by distance anyway... they
may want to do only a bounding-box type filter for greater
performance.

We should keep both concepts (bounding box filter and distance filter)
regardless of how the distance filter is implemented.

-Yonik
Apache Lucene Eurocon 2010
18-21 May 2010 | Prague

---------------------------------------------------------------------
To unsubscribe, e-mail: java-dev-unsubscribe@lucene.apache.org
For additional commands, e-mail: java-dev-help@lucene.apache.org


Mime
View raw message