Re: [Geojson] Question on Redundancy
Sean Gillies <sean.gillies@gmail.com> Thu, 06 July 2017 17:28 UTC
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From: Sean Gillies <sean.gillies@gmail.com>
Date: Thu, 06 Jul 2017 19:27:59 +0200
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To: Chris Goodman <Chris.Goodman@objectconsulting.com.au>
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Subject: Re: [Geojson] Question on Redundancy
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Hello Chris, The GeoJSON authors and working group didn't identify a use case for a linear ring outside the context of a polygon and did not define the type. I would have to go back through the archives to see why redundancy was settled upon, but I suspect it had to do with a desire to distinguish between closed curves and curves accidentally left open. I hope this helps, On Mon, Jul 3, 2017 at 3:06 AM, Chris Goodman < Chris.Goodman@objectconsulting.com.au> wrote: > Hello, In the IETF standard https://tools.ietf.org/html/ > rfc7946#section-3.1.6 3.1.6 > <https://tools.ietf.org/html/rfc7946#section-3.1.6>. Polygon > > > > > > To specify a constraint specific to Polygons, it is useful to > > introduce the concept of a linear ring: > > > > o A linear ring is a closed LineString with four or more positions. > > > > o The first and last positions are equivalent, and they MUST contain > > identical values; their representation SHOULD also be identical. > > > > > > The last point is redundant. Why didn’t the standard define a LinearRing > as a new type and avoid the redundancy? > > > > For example, in an IOT LoRa network, the low data and small packet size > places constraints on the data. The redundancy could be avoided if we > assume the closing coordinate has the same values as the first. > > > > Regards, Chris > > > > > > *Chris Goodman* > > Supervising Consultant > M: +61 419 482 620 <+61%20419%20482%20620> > > Office: +61 3 8615 4500 <+61%203%208615%204500> > > Web: *www.objectconsulting.com.au <http://www.objectconsulting.com.au>* > > Email: chris.goodman@objectconsulting.com.au > > > > _______________________________________________ > GeoJSON mailing list > GeoJSON@ietf.org > https://www.ietf.org/mailman/listinfo/geojson > > -- Sean Gillies
- [Geojson] Question on Redundancy Chris Goodman
- Re: [Geojson] Question on Redundancy Sean Gillies
- Re: [Geojson] Question on Redundancy Chris Goodman