[postgis-users] GeomUnion problem

[Brent Wood]

Hi,

I'm not sure what the problem is here, hopefully someone can help.

I have some polygons cropped to cell boundaries. (select intersection...)
I want to generate the geomunion of these for each cell, which seems
straightforward, but GEOS is throwing an error...

   select astext(geomunion(track_cell_geom)) from effort_cells3 where cell_id =
73721;
NOTICE:  TopologyException: no outgoing dirEdge found
(168.077,-40.1961,-40.1961)
ERROR:  GEOS union() threw an error!



Can anyone say what this means & what I need to do to work around it?

Thanks,

  Brent Wood