[postgis-devel] [PostGIS] #1650: Invalid edge (no two distinct vertices exist)

[PostGIS]

#1650: Invalid edge (no two distinct vertices exist)
----------------------+-----------------------------------------------------
 Reporter:  lrssvt    |       Owner:  strk         
     Type:  defect    |      Status:  new          
 Priority:  medium    |   Milestone:  PostGIS 2.0.0
Component:  topology  |     Version:  2.0.x        
 Keywords:            |  
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Comment(by strk):

 One of your edges is shorter than 2, what do you think postgis should do
 in that case ?
 {{{
 =# select id, st_length(wkb_geometry) from test.pipes;
  id |    st_length
 ----+------------------
   1 |  1.6405966228982
   2 | 129.304797905447
 (2 rows)
 }}}

 I guess these are the options:

  1. Add _nothing_ to the topology, return a NULL TopoGeometry
  1. Add _nothing_ to the topology, return an EMPTY TopoGeometry
  1. Add a single node to the topology, return a NULL TopoGeometry
  1. Add a single node to the topology, return an EMPTY TopoGeometry
  1. Add a single node to the topology, return a Puntal TopoGeometry

 Note that a Puntal TopoGeometry will fail to be inserted into a Lineal
 layer.

 I'm not sure this is to be considered a bug.

-- 
Ticket URL: <http://trac.osgeo.org/postgis/ticket/1650#comment:1>
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