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From Ted Dunning <ted.dunn...@gmail.com>
Subject Re: Will it go 'round in circles?
Date Fri, 07 Aug 2015 21:04:41 GMT
There you go.

Another application.



On Fri, Aug 7, 2015 at 1:43 PM, Mike Carey <dtabass@gmail.com> wrote:

> AND:  What if NASA wants to use us to store its database of crop circles?
> :-)
>
> On 8/7/15 11:47 AM, Ted Dunning wrote:
>
>> On Fri, Aug 7, 2015 at 3:23 AM, Chris Hillery <chillery@hillery.land>
>> wrote:
>>
>> I've noticed that several geospatial serialization formats (at least
>>> "well-known text" and GeoJSON) omit "circle" from their list of basic
>>> geometric forms, even when they have numerous more complex types such as
>>> multi-curves. This led me to here:
>>> http://forums.mysql.com/read.php?23,148162,152625#msg-152625
>>>
>>> which offers a reasonably compelling argument for why "circle" is not a
>>> reasonable shape to discuss in geospatial contexts (loosely, because
>>> there's no consistent way to map that to a spherical coordinate system).
>>>
>>> Actually, that argument is super-weak.  It also implies that you
>> shouldn't
>> have lines (they aren't straight after projection) or squares (they aren't
>> square after projection). But lines and squares both before and after
>> projection are very handy.
>>
>> Circles are useful in many contexts. Drawing the visible horizon for a
>> particular observer is a great example.  The flight range of an airplane
>> is
>> another case.  Positional error bounds with Gaussian errors is another.
>>
>> Yes. You can approximate it using splines or polygons.  But you can
>> approximate anything that way.
>>
>>
>

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