[postgis-devel] [PostGIS] #2066: ST_DumpPoints may return latitude just over 90 depending on execution order

[PostGIS]

#2066: ST_DumpPoints may return latitude just over 90 depending on execution order
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 Reporter:  realityexists  |       Owner:  pramsey      
     Type:  defect         |      Status:  new          
 Priority:  medium         |   Milestone:  PostGIS 2.1.0
Component:  postgis        |     Version:  trunk        
 Keywords:                 |  
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Comment(by realityexists):

 OK, tested on Windows 7 x64, r10691, PostgreSQL 9.2.1. The original
 problem no longer occurs, but this:

 {{{
 SELECT ST_AsText(ST_SnapToGrid(ST_Transform(ST_GeomFromText('POINT(180
 50)', 4269), 4326), 0.00001)::geography)
 }}}

 returns POINT(-180 50) instead of POINT(180 50) as it used to. Note that
 if you remove the cast to geography it still returns "POINT(180 50)". I
 suspect it's something similar to the original problem with the longitude
 being "just over" 180.

 I think the behaviour of ST_AsText and other string-returning functions
 should be consistent with ::geography, ie. if the value is close enough to
 180 for ST_AsText to display it as "180" then it's also close enough for
 ::geography to convert it to 180, not -180. Anything else just gets really
 confusing.

-- 
Ticket URL: <http://trac.osgeo.org/postgis/ticket/2066#comment:3>
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