[postgis-tickets] [PostGIS] #2549: ST_Intersection throws error when ST_IsValid returns true

[PostGIS]

#2549: ST_Intersection throws error when ST_IsValid returns true
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  Reporter:  nightdrift  |       Owner:  pramsey      
      Type:  defect      |      Status:  closed       
  Priority:  high        |   Milestone:  PostGIS 2.1.2
 Component:  postgis     |     Version:  2.1.x        
Resolution:  wontfix     |    Keywords:               
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Changes (by pramsey):

  * status:  new => closed
  * resolution:  => wontfix


Comment:

 Using your WKT representations (your WKB seem to be muddled) I do get
 validity errors
 {{{
 postgis22=# select st_isvalid(g) from inter;
 NOTICE:  Ring Self-intersection at or near point 139.456321226
 -20.897800989
  st_isvalid
 ------------
  t
  f
 }}}
 probably your WKB don't have the errors, but the WKT errors are pointing
 up that the coordinates are a hair's breadth away from having them (and
 the slight rounding that the WKT caused is showing them up). Try a very
 very very fine snap to grid, followed by a call to makevalid. Might not
 work, but also might. Also consider some simplification and makevalid,
 since probably you aren't that concerned about an "exact" answer.

 This is yet another case where GEOS snap rounding would be nice to have.

-- 
Ticket URL: <http://trac.osgeo.org/postgis/ticket/2549#comment:1>
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