[postgis-users] selection of data in WGS84 lat/lon over the noth pole

[Brian Modra]

2009/9/28 Malm Paul <paul.malm at saabgroup.com>:
> Hi list,
> I would like to select data over the north pole inside a polygon of lat/lon coordinates
> For selection I create a polygon from theese coordinates
>
> 1) 80, -170
> 2) 80, 170
> 3) 75, 10
> 4) 75, -10
>
> But is seems that the objects found are from around the pole instead of over the pole, it does not find any objects over 80°
> Is ther a way to get around this?

This is a wild guess, having not looked at the PostGIS code, and not
knowing how your data is stored, but I wonder if you need to put in
more coords, because depending on the prjection, the lines joining
those 4 points could be kind of weird.

e.g.
80 0, 80 20, 80 40, 80 50, 80 60... 80 180, 80 -160, 80 -140 ... 80 0



> Kind regards,
> Paul
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