[postgis-users] postgis topology

[Ludovic Granjon]

Thanks all, so

if I try like Sandro said :

UPDATE ec SET geom = ST_SnapToGrid(geom, 1);
UPDATE ec SET topo_geom = toTopoGeom(geom, 'ec_topo', 1, 1.0);

I have this error :
SQL/MM Spatial exception - curve not simple

If i increase tolerance parameter, I have :
ERREUR: SQL/MM Spatial exception - point not on edge

With Rémi's solution :

UPDATE ec SET topo_geom = rc_totopogeomwithouterrors(geom, 'ec_topo', 1, 
1.0);

It works with a lot (76) of NOTICE:  this geometry can't be converted to 
topogeom :
but other geometry worked

so it's better

Now, I have to know why some geometry doesn't work

Maybe I have to explain more what I'm trying to do

My data overlap and there are not clean. Sometimes polygon should have 
jointly vertex but it's not the case. (I join a image)

I want to snap when the distance is smaller than tolerance and intersect 
polygon when they overlap.

Do you think that use topology is the best way to do that ?

Thanks a lot

regards

Ludovic





Le 15/01/2014 13:49, Rémi Cura a écrit :
> -- Function: public.rc_totopogeomwithouterrors(geometry, character 
> varying, integer, double precision)
>
> -- DROP FUNCTION public.rc_totopogeomwithouterrors(geometry, character 
> varying, integer, double precision);
>
> CREATE OR REPLACE FUNCTION public.rc_totopogeomwithouterrors(ageom 
> geometry, atopology character varying, alayer integer, atolerance 
> double precision DEFAULT 0)
>   RETURNS topogeometry AS
> $BODY$
> DECLARE
>   layer_info RECORD;
>   topology_info RECORD;
>   rec RECORD;
>   tg topology.TopoGeometry;
>   elems topology.TopoElementArray = '{{0,0}}';
>   sql TEXT;
>   typ TEXT;
>   tolerance FLOAT8;
> BEGIN
>
> raise notice 'ageom : %',ST_AsText(ageom);
>   -- Get topology information
>   BEGIN
>     SELECT *
>     FROM topology.topology
>       INTO STRICT topology_info WHERE name = atopology;
>   EXCEPTION
>     WHEN NO_DATA_FOUND THEN
>       RAISE EXCEPTION 'No topology with name "%" in topology.topology',
>         atopology;
>   END;
>
>   -- Get tolerance, if 0 was given
>   tolerance := COALESCE( NULLIF(atolerance, 0), 
> topology._st_mintolerance(atopology, ageom) );
>
>   -- Get layer information
>   BEGIN
>     SELECT *, CASE
>       WHEN feature_type = 1 THEN 'puntal'
>       WHEN feature_type = 2 THEN 'lineal'
>       WHEN feature_type = 3 THEN 'areal'
>       WHEN feature_type = 4 THEN 'mixed'
>       ELSE 'unexpected_'||feature_type
>       END as typename
>     FROM topology.layer l
>       INTO STRICT layer_info
>       WHERE l.layer_id = alayer
>       AND l.topology_id = topology_info.id <http://topology_info.id>;
>   EXCEPTION
>     WHEN NO_DATA_FOUND THEN
>       RAISE EXCEPTION 'No layer with id "%" in topology "%"',
>         alayer, atopology;
>   END;
>
>   -- Can't convert to a hierarchical topogeometry
>   IF layer_info.level > 0 THEN
>       RAISE EXCEPTION 'Layer "%" of topology "%" is hierarchical, 
> cannot convert to it.',
>         alayer, atopology;
>   END IF;
>
>
>   --
>   -- Check type compatibility and create empty TopoGeometry
>   -- 1:puntal, 2:lineal, 3:areal, 4:collection
>   --
>   typ = geometrytype(ageom);
>   IF typ = 'GEOMETRYCOLLECTION' THEN
>     --  A collection can only go collection layer
>     IF layer_info.feature_type != 4 THEN
>       RAISE EXCEPTION
>         'Layer "%" of topology "%" is %, cannot hold a collection 
> feature.',
>         layer_info.layer_id, topology_info.name 
> <http://topology_info.name>, layer_info.typename;
>     END IF;
>     tg := topology.CreateTopoGeom(atopology, 4, alayer);
>   ELSIF typ = 'POINT' OR typ = 'MULTIPOINT' THEN -- puntal
>     --  A point can go in puntal or collection layer
>     IF layer_info.feature_type != 4 and layer_info.feature_type != 1 THEN
>       RAISE EXCEPTION
>         'Layer "%" of topology "%" is %, cannot hold a puntal feature.',
>         layer_info.layer_id, topology_info.name 
> <http://topology_info.name>, layer_info.typename;
>     END IF;
>     tg := topology.CreateTopoGeom(atopology, 1, alayer);
>   ELSIF typ = 'LINESTRING' or typ = 'MULTILINESTRING' THEN -- lineal
>     --  A line can go in lineal or collection layer
>     IF layer_info.feature_type != 4 and layer_info.feature_type != 2 THEN
>       RAISE EXCEPTION
>         'Layer "%" of topology "%" is %, cannot hold a lineal feature.',
>         layer_info.layer_id, topology_info.name 
> <http://topology_info.name>, layer_info.typename;
>     END IF;
>     tg := topology.CreateTopoGeom(atopology, 2, alayer);
>   ELSIF typ = 'POLYGON' OR typ = 'MULTIPOLYGON' THEN -- areal
>     --  An area can go in areal or collection layer
>     IF layer_info.feature_type != 4 and layer_info.feature_type != 3 THEN
>       RAISE EXCEPTION
>         'Layer "%" of topology "%" is %, cannot hold an areal feature.',
>         layer_info.layer_id, topology_info.name 
> <http://topology_info.name>, layer_info.typename;
>     END IF;
>     tg := topology.CreateTopoGeom(atopology, 3, alayer);
>   ELSE
>       -- Should never happen
>       RAISE EXCEPTION
>         'Unsupported feature type %', typ;
>   END IF;
>
>   -- Now that we have a topogeometry, we loop over distinct components
>   -- and add them to the definition of it. We add them as soon
>   -- as possible so that each element can further edit the
>   -- definition by splitting
>
> --modified to catch errors:
> BEGIN
>
>   FOR rec IN SELECT DISTINCT id(tg), alayer as lyr,-- geom,
>     CASE WHEN ST_Dimension(geom) = 0 THEN 1
>          WHEN ST_Dimension(geom) = 1 THEN 2
>          WHEN ST_Dimension(geom) = 2 THEN 3
>     END as type,
>     CASE WHEN ST_Dimension(geom) = 0 THEN
>            topology.topogeo_addPoint(atopology, geom, tolerance)
>          WHEN ST_Dimension(geom) = 1 THEN
>            topology.topogeo_addLineString(atopology, geom, tolerance)
>          WHEN ST_Dimension(geom) = 2 THEN
>            topology.topogeo_addPolygon(atopology, geom, tolerance)
>     END as primitive
>     FROM (SELECT (ST_Dump(ageom)).geom) as f
>     WHERE NOT ST_IsEmpty(geom)
>   LOOP
>   --raise notice 'coucou, tg : %, geom %',rec.id <http://rec.id>, 
> ST_AsText(rec.geom);
>     -- TODO: consider use a single INSERT statement for the whole thing
>     sql := 'INSERT INTO ' || quote_ident(atopology)
>         || '.relation(topogeo_id, layer_id, element_type, element_id) 
> VALUES ('
>         || rec.id <http://rec.id> || ',' || rec.lyr || ',' || rec.type
>         || ',' || rec.primitive || ')';
>     EXECUTE sql;
>   END LOOP;
>
>   RETURN tg;
> EXCEPTION
>     WHEN SQLSTATE 'P0001' THEN
>         RAISE NOTICE 'this geometry can''t be converted to topogeom : %
> doing nothing',ageom;
> RETURN NULL;
> END;
> END
> $BODY$
>   LANGUAGE plpgsql VOLATILE STRICT
>   COST 100;
> ALTER FUNCTION public.rc_totopogeomwithouterrors(geometry, character 
> varying, integer, double precision)
>   OWNER TO postgres;

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/postgis-users/attachments/20140115/dc017964/attachment.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: ludovic_granjon.vcf
Type: text/x-vcard
Size: 149 bytes
Desc: not available
URL: <http://lists.osgeo.org/pipermail/postgis-users/attachments/20140115/dc017964/attachment.vcf>