[postgis-users] Intersection TopologyException

[Luís Miguel Royo Pérez]

Thank you Rémi,

I think I have mixed up some issues. I thought the error was produced by 
the problematic layer, but is mapa_ruido_dia the problem, it's a 
completly mess :(

I have tried to clean the layer, but I don't know how exactly should I 
proceed.

Can anyone lead me in this task with some links or tips?

Thank you!!



On 12/02/2014 11:49 AM, Rémi Cura wrote:
> Hey,
> some common answer about precision issue :
>
>
> 1. : offset your coordinate to gain in precision :
> 723120.23091093975 4379700.195452339 -> 120.23091093975XXX , 
> 700.195452339XXXX
> 2. snap to grid you input data
>
> 3. check that your input geoms are valid : st_isvalid : st_makevalid()
>
> Cheers,
> Rémi-C
>
> 2014-12-02 11:45 GMT+01:00 Luís Miguel Royo Pérez 
> <luis.miguel.royo at gmail.com <mailto:luis.miguel.royo at gmail.com>>:
>
>     Hi everyone,
>
>     I'm trying to perform a quite simple analysis in Postgis, but I'm
>     facing a TopologyException where there's no features.
>
>     You can find the data I'm using in this link
>     <https://mega.co.nz/#%21pFgnCBoA%21zx-Tb78nPGzL7Fcbw7dMheSbIrMfRJjJ9yV1Qv7Wx6o>.
>
>     What I try to do is the next:
>
>       * First I want to create a buffer for emt_paradas, and the layer
>         valenbisi, and then intersect them, the result I will call
>         "intersect_1".
>
>     |     select  st_intersection(buf_emt.st_union,buf_valenbisi.st_union)
>          from
>          (SELECT  ST_union(st_buffer(emt_paradas.geom, 200)) FROM emt_paradas )as buf_emt,
>          (SELECT  ST_union(st_buffer(valenbisi.geom, 200)) FROM valenbisi )as buf_valenbisi|
>
>       * Second, I want to create a buffer for carril_bici, and
>         intersect with "intersect_1". The result I will call
>         "intersect_2".
>
>     |     select  st_intersection(buf_carril_bici.st_union,inter_emt_valenbisi.st_intersection)
>          from
>          (select  st_intersection(buf_emt.st_union,buf_valenbisi.st_union)
>          from
>          (SELECT  ST_union(st_buffer(emt_paradas.geom, 200)) FROM emt_paradas )as buf_emt,
>          (SELECT  ST_union(st_buffer(valenbisi.geom, 200)) FROM valenbisi )as buf_valenbisi) as intersect_1|
>
>       * Third, I want to create a buffer for layer ocio and make a
>         difference with "intersect_2". The result I will call: "diff_1".
>
>     |     select  st_difference(intersec_2.st_intersection, buf_ocio.st_union)
>          from
>          (select  st_intersection(buf_carril_bici.st_union,inter_emt_valenbisi.st_intersection)
>          from
>          (select  st_intersection(buf_emt.st_union,buf_valenbisi.st_union)
>          from
>          (SELECT  ST_union(st_buffer(emt_paradas.geom, 200)) FROM emt_paradas )as buf_emt,
>          (SELECT  ST_union(st_buffer(valenbisi.geom, 200)) FROM valenbisi )as buf_valenbisi) as inter_emt_valenbisi,
>          (SELECT  ST_union(st_buffer(carril_bici.geom, 200)) FROM carril_bici )as buf_carril_bici) as intersectionEMT_valenbisi_carrilBici,
>          (SELECT  ST_union(st_buffer(ocio.geom, 250)) FROM ocio )as buf_ocio|
>
>       * Finnaly I want to intersect "diff_1" with layer
>         mapa_ruido_dia, ideally where the field gridcode equals one or
>         two.
>
>     |     select 1 as id, st_intersection(diff_1.st_difference, mapa_ruido_dia.geom)
>          from
>          (select  st_difference(intersectionEMT_valenbisi_carrilBici.st_intersection, buf_ocio.st_union)
>          from
>          (select  st_intersection(buf_carril_bici.st_union,inter_emt_valenbisi.st_intersection)
>          from
>          (select  st_intersection(buf_emt.st_union,buf_valenbisi.st_union)
>          from
>          (SELECT  ST_union(st_buffer(emt_paradas.geom, 200)) FROM emt_paradas )as buf_emt,
>          (SELECT  ST_union(st_buffer(valenbisi.geom, 200)) FROM valenbisi )as buf_valenbisi) as inter_emt_valenbisi,
>          (SELECT  ST_union(st_buffer(carril_bici.geom, 200)) FROM carril_bici )as buf_carril_bici) as intersectionEMT_valenbisi_carrilBici,
>          (SELECT  ST_union(st_buffer(ocio.geom, 250)) FROM ocio )as buf_ocio)as diff_1, mapa_ruido_dia
>           where mapa_ruido_dia.gridcode='1' or mapa_ruido_dia.gridcode='2'
>
>     |
>
>     Is in this last one query when Postgis show me the TopologyException
>
>     |> Error performing intersection: TopologyException: Input geom 1 is
>     > invalid: Self-intersection at or near point 723120.23091093975
>     > 4379700.195452339 at 723120.23091093975 4379700.195452339
>
>
>     Any ideas? Thank you very much!|
>
>
>     _______________________________________________
>     postgis-users mailing list
>     postgis-users at lists.osgeo.org <mailto:postgis-users at lists.osgeo.org>
>     http://lists.osgeo.org/cgi-bin/mailman/listinfo/postgis-users
>
>
>
>
> _______________________________________________
> postgis-users mailing list
> postgis-users at lists.osgeo.org
> http://lists.osgeo.org/cgi-bin/mailman/listinfo/postgis-users

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/postgis-users/attachments/20141202/d07b65c4/attachment.html>