[postgis-devel] [PostGIS] #1789: ST_CreateTopoGeo: ERROR: Invalid edge (no two distinct vertices exist)

[PostGIS]

#1789: ST_CreateTopoGeo: ERROR:  Invalid edge (no two distinct vertices exist)
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 Reporter:  strk      |       Owner:  strk         
     Type:  defect    |      Status:  new          
 Priority:  medium    |   Milestone:  PostGIS 2.0.1
Component:  topology  |     Version:  2.0.x        
 Keywords:            |  
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 I was playing with hexagon grids and knowing irrational numbers
 approximation would have introduced slight discrepancies I thought to take
 a look using PostGIS topology.

 To be honest I did expect problems :)

 Well, here's the problem:
 ERROR:  Invalid edge (no two distinct vertices exist)

 To reproduce:

 1. load
 https://github.com/Vizzuality/cartodb/blob/develop/lib/sql/CDB_Hexagon.sql
 1. create a grid table: create table hgrid10 as select
 CDB_HexagonGrid(ST_MakeEnvelope(-180, -90, 180, 90), 10) as geom;
 1. create a topology out of it: select createtopology('hexagon_topo');
 select ST_CreateTopoGeo('hexagon_topo', st_collect(geom)) from hgrid10;

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Ticket URL: <http://trac.osgeo.org/postgis/ticket/1789>
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