asterixdb-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Chris Hillery <chill...@hillery.land>
Subject Re: Will it go 'round in circles?
Date Sat, 08 Aug 2015 07:13:04 GMT
Ok, sounds like the consensus is that we want to keep circle. That's fine
with me. To bring the conversation full circle (narf!), now the question
goes back to how best to represent that type in JSON, given that the
obvious options don't support it... but, that conversation should continue
on the original thread.

Thanks!
Ceej
aka Chris Hillery

On Fri, Aug 7, 2015 at 10:41 PM, Chen Li <chenli@gmail.com> wrote:

> I second Ted's argument.  The reason on
> http://forums.mysql.com/read.php?23,148162,152625#msg-152625 is very
> weak, since following that logic there will be no 100% lines or
> rectangles on the surface of the earth.  But these shapes are very
> useful.
>
> I am sure there are use cases for circles, such as the Apple's new
> headquarters.  A related question is: what's the overhead of
> implementing and maintaining this type?
>
> Chen
>
> On Fri, Aug 7, 2015 at 2:04 PM, Ted Dunning <ted.dunning@gmail.com> wrote:
> > 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.
> >>>
> >>>
> >>
>

Mime
  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message