[postgis-users] GeomUnion problem

[Brent Wood]

--- Paul Ramsey <pramsey at refractions.net> wrote:

<snip>

> > Or is there some way of tweaking the underlying polygons to be  
> > combined to address the problem?
> 
> Martin gave that recipe:  buffer(geomunion(buffer(a,0.1),buffer(b, 
> 0.1)),-0.1)



Hi guys,

It looks like I'll need to upgrade GEOS to v3, as the buffer command has failed
to fix the problem with geomunion:

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
select buffer(geomunion(buffer(track_cell_geom,0.1)),-0.1) 
from effort_cells3 
where cell_id = 73722 
  and isvalid(track_cell_geom);

NOTICE:  TopologyException: no outgoing dirEdge found
(168.129,-40.0659,-40.0659)
ERROR:  GEOS union() threw an error!

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

Cheers,

  Brent