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Thread @ natural earth data forum: http://www.naturalearthdata.com/forums/topic.php?id=81<br><br>E<br><br><br>> Date: Fri, 7 Jan 2011 09:03:44 -0600<br>> From: david.fawcett@gmail.com<br>> To: postgis-users@postgis.refractions.net<br>> Subject: Re: [postgis-users] Trying to import natural earth data into<br>> <br>> Since it looks like there is a significant problem with the Natural<br>> Earth data and many people are attempting to clean the data up in<br>> parallel, has anyone approached the Natural Earth folks and made them<br>> aware of the problem so they can hopefully fix the source data?<br>> <br>> David.<br>> <br>> On Fri, Jan 7, 2011 at 12:51 AM, Brian Hamlin <maplabs@light42.com> wrote:<br>> > regarding GRASS and PostGIS on Natural Earth vectors<br>> ><br>> > unfortunately, it seems that a v.in.ogr / v.out.ogr round trip<br>> > does *not* clean the vectors completely, as tested by st_isValid()<br>> ><br>> > --<br>> > GRASS trunk (7)<br>> > PostGIS 1.5.3<br>> > current Natural Earth shp files,<br>> ><br>> > tested table: 10m_urban_areas<br>> > 12,022 polys<br>> ><br>> > st_isValid() shows 31 errors<br>> > self-intersection and ring self-intersection<br>> ><br>> > PostGIS ST_Buffer(0) creates output<br>> > that is clean of these errors, according to PostGIS<br>> ><br>> > GRASS 7 v.in.ogr / v.out.ogr creates output<br>> > that still has 14 polys with "ring self-intersection"<br>> > according to PostGIS<br>> > -<br>> ><br>> > ps -<br>> > this is true with or without benefit of the mighty "for" loop<br>> ><br>> > best regards<br>> > -Brian<br>> ><br>> > ==<br>> > Brian Hamlin<br>> > planetwork.net<br>> > OSGeo California Chapter<br>> > (415) 717-4462 cell<br>> ><br>> > _______________________________________________<br>> > postgis-users mailing list<br>> > postgis-users@postgis.refractions.net<br>> > http://postgis.refractions.net/mailman/listinfo/postgis-users<br>> ><br>> _______________________________________________<br>> postgis-users mailing list<br>> postgis-users@postgis.refractions.net<br>> http://postgis.refractions.net/mailman/listinfo/postgis-users<br> </body>
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