(no subject)

From: Patrick Dowler <patrick.dowler-at-nrc-cnrc.gc.ca>
Date: Wed, 14 May 2008 15:29:29 -0700


On 2008-5-14 14:23, Francois Ochsenbein wrote:
> Well, the self-join example of Jeff and Pat is exactly what I feel would be
> more easily expressed with a sphericalDistance function:

For that example they happen to be equivalent because the only shape is a circle. But we know there are shapes (the bounds of observations, surveys, etc) that are not circles... so we need the generality of INTERSECTS.

-- 

Patrick Dowler
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Received on 2008-05-15Z00:30:02