[postgis-tickets] [PostGIS] #2183: ST_SimplifyPreserveTopology does not preserve the topology

[PostGIS]

#2183: ST_SimplifyPreserveTopology does not preserve the topology
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 Reporter:  pcav      |       Owner:  strk         
     Type:  defect    |      Status:  new          
 Priority:  medium    |   Milestone:  PostGIS 2.0.3
Component:  topology  |     Version:  2.0.x        
 Keywords:            |  
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 SELECT ST_ChangeEdgeGeom('province_topo', edge_id,
 ST_SimplifyPreserveTopology(geom, 500))
 topo2->  FROM province_topo.edge;
 ERROR:  Invalid edge (no two distinct vertices exist)

 whereas:

  SELECT ST_ChangeEdgeGeom(
   'province_topo', edge_id,
    ST_SimplifyPreserveTopology(geom, 500))
   FROM province_topo.edge
   WHERE ST_IsValid(
   ST_SimplifyPreserveTopology(geom, 500));

 completes the task, but drops all islands. See attached shapefile.

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Ticket URL: <http://trac.osgeo.org/postgis/ticket/2183>
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