Re: [Geojson] Question on Redundancy

[Sean Gillies <[e-mail]>]

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 <
[e-mail]> 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:  [phone] <+61%20419%20482%20620>
>
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>
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>
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-- 
Sean Gillies