[postgis-users] ST_Split with Multilinestring

[Birgit Laggner]

Hi Rémi,

thank you for sharing your function. In the meantime I seem to have 
solved the problem by combining the st_split function with a function 
from an old use case:

CREATE OR REPLACE FUNCTION ST_SplitPolygon(poly geometry, blade 
geometry) RETURNS geometry AS
$$
declare
out_geom geometry;
begin
begin
out_geom := st_split(poly, blade);
exception when internal_error then
out_geom := ST_Collect((d).geom) FROM (SELECT 
ST_Dump(ST_Polygonize(ST_Union(ST_Boundary(poly), blade))) AS d) f WHERE 
ST_Area(ST_Intersection(poly, (d).geom)) / ST_Area((d).geom) >= 1 - 1e-10;
end;
return out_geom;
end;
$$
LANGUAGE plpgsql IMMUTABLE STRICT COST 100;

But I will definitely give your function a try and compare the results!

Thanks again! Regards,

Birgit

Am 16.06.2016 um 10:18 schrieb Rémi Cura:
> Hey,
> I wrote a multi-friendly st_split a while ago.
> Maybe it will help you:
> https://github.com/Remi-C/PPPP_utilities/blob/master/postgis/rc_split_multi.sql
>
> Cheers,
> Rémi-C
>
> 2016-06-15 19:19 GMT+02:00 Birgit Laggner, vTI 
> <birgit.laggner at thuenen.de <mailto:birgit.laggner at thuenen.de>>:
>
>     Hi Sandro,
>
>     yes, I read so, too. But, our database has PostGIS version:
>     "POSTGIS="2.2.1 r14555" GEOS="3.5.0-CAPI-1.9.0 r4084" PROJ="Rel.
>     4.9.1, 04 March 2015" GDAL="GDAL 1.11.2, released 2015/02/10"
>     LIBXML="2.9.2" LIBJSON="0.11.99" TOPOLOGY RASTER" and I still get
>     that error. Any idea why?
>
>     Regards,
>
>     Birgit
>
>
>     Am 15.06.2016 um 19:02 schrieb Sandro Santilli:
>
>         On Tue, Jun 14, 2016 at 02:52:52PM +0200, Birgit Laggner wrote:
>
>             ERROR: Splitting a Polygon by a MultiLineString is unsupported
>
>         Support for this functionality was added in PostGIS-2.2.0
>
>         --strk;
>
>
>
>     _______________________________________________
>     postgis-users mailing list
>     postgis-users at lists.osgeo.org <mailto:postgis-users at lists.osgeo.org>
>     http://lists.osgeo.org/mailman/listinfo/postgis-users
>
>
>
>
> _______________________________________________
> postgis-users mailing list
> postgis-users at lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/postgis-users

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/postgis-users/attachments/20160616/91b99382/attachment.html>