[postgis-users] Union fails on 2389 linestrings.

[Jeff Adams]

The coords are lat/lon, so simplifying by 0.001 is something like 100
meters...  That's too coarse for my project.

On Thu, Jul 29, 2010 at 3:49 AM, Maxime van Noppen <maxime at altribe.org>wrote:

> On 07/28/2010 10:15 PM, Jeff Adams wrote:
>
>> OK, I finally have it down to a manageable use case.  Union these 16
>> linestrings, you get a topology exception.  Remove any one of them, you
>> don't.  What the heck can I do about this?  Simplifying and snapping to
>> grid, at any reasonable precision, did not help my larger real data (I
>> didn't try with this little test case).
>>
>> Is there any chance that ST_Union has a bug?  Isn't it supposed to be
>> adding the node it complains is missing?
>>
>
> I got it working by simplifying the geometries:
>
>  st_union(st_simplify(geom, 0.001))
>
> if it is of any help.
>
> --
> Maxime
>
> _______________________________________________
> postgis-users mailing list
> postgis-users at postgis.refractions.net
> http://postgis.refractions.net/mailman/listinfo/postgis-users
>



-- 
Jeff Adams
Azavea (formerly Avencia)  |  T: 215.701.7717  |  F: 215.925.2663
www.azavea.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/postgis-users/attachments/20100729/bbe193b7/attachment.html>