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Re: Ellipse Data Type? Best practices for elliptical data? [Oracle 9i Spatial]

From: Hans Forbrich <forbrich_at_yahoo.net>
Date: Tue, 18 May 2004 18:47:11 GMT
Message-ID: <PSsqc.11702$RM.7679@edtnps89>


C Wilks wrote:

>
> I will just be using a standard geodetic spatial reference system,
> probably WGS84 from what I can gather so far. I'm just trying to store
> geodetic ellipses, and then compare them with other shapes using the
> standard spatial predicates.

Sounds intriguing.

Since coord systems & their projections are based on datum that reference ellipsoids, I can image the error calc's involved when your ellipse doesn't agree with the datum will be hairy.

Mind expanding why you are doing this? Perhaps off-list to contact_forbrich at telus planet dot net, without spaces or contact_

Nevertheless, since 9i geodetics don't directly support arcs, you will need to approximate your ellipse. You might find the description of the arc densification function useful.

/Hans Received on Tue May 18 2004 - 13:47:11 CDT

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