[postgis-tickets] [PostGIS] #5392: Aggregate ST_Union fails to join some "circles" when radius is too large

[PostGIS]

#5392: Aggregate ST_Union fails to join some "circles" when radius is too large
----------------------+---------------------------
  Reporter:  rotten   |      Owner:  pramsey
      Type:  defect   |     Status:  new
  Priority:  medium   |  Milestone:  PostGIS 3.3.4
 Component:  postgis  |    Version:  3.3.x
Resolution:           |   Keywords:
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Comment (by robe):

 Thanks for the self-contained examples.  I am able to replicate this issue
 too and get


 {{{
 ERROR:  lwgeom_unaryunion_prec: GEOS Error: TopologyException: side
 location conflict at -174.563034509468 -18.071220344085667. This can occur
 if the input geometry is invalid.

 }}}

 Regarding your email note about Union aggregate use being rare, it's
 probably one of the most commonly used functions in PostGIS.  Sadly this
 problem is one of the most common people run across, and GEOS project is
 working hard to remove instances of this.

 {{{
 POSTGIS="3.4.0dev 3.3.0rc2-955-g4ace89312" [EXTENSION] PGSQL="160"
 GEOS="3.12.0dev-CAPI-1.18.0" PROJ="8.2.1" LIBXML="2.9.14" LIBJSON="0.12"
 LIBPROTOBUF="1.2.1" WAGYU="0.5.0 (Internal)"
 }}}


 My geos 3.12 is a couple of weeks old, so I'll need to check on this to
 see if newer has a fix for it.

 This is what Martin on GEOS and PostGIS teams) likes to call a
 "robustness" issue.

 Can you output what your below returns


 {{{
 SELECT postgis_full_version();
 }}}

 Ultimately I think this is something that needs to be fixed on the GEOS
 side.
-- 
Ticket URL: <https://trac.osgeo.org/postgis/ticket/5392#comment:2>
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