[postgis-devel] [PostGIS] #575: ST_Union fails on a group of linestrings.

[PostGIS]

#575: ST_Union fails on a group of linestrings.
-------------------------+--------------------------------------------------
 Reporter:  jeffadams78  |       Owner:  pramsey      
     Type:  defect       |      Status:  new          
 Priority:  medium       |   Milestone:  PostGIS 1.5.2
Component:  postgis      |     Version:  1.5.X        
 Keywords:               |  
-------------------------+--------------------------------------------------
 When I attempt to union these 16 linestrings (quite long, so I attached as
 a file), I get the following error:

 {{{
 NOTICE:  TopologyException: found non-noded intersection between
 LINESTRING (-118.323 33.7869, -118.323 33.7869) and LINESTRING (-118.323
 33.7869, -118.323 33.7869) at -118.323 33.7869



 ERROR:  GEOS union() threw an error!

 ********** Error **********


 ERROR: GEOS union() threw an error!
 SQL state: XX000
 }}}

 This seems like a bug.  Isn't it supposed to be adding the node it
 complains is missing?  This same union works fine in JTS.


 NOTE: The linestrings printed in the error message are not in fact zero-
 length, they appear that way due to the truncation of significant digits
 in the error output.  I tried reprojecting my data (the original data, not
 this particular tiny set) into 3310 and got the same error, but then the
 error message printed enough significant digits to make it clear they are
 very short, but not zero-length.

-- 
Ticket URL: <http://trac.osgeo.org/postgis/ticket/575>
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