[postgis-users] Intersection errors out with null directed edge

[Chris Hermansen]

Hello again;

So with GEOS 3.0.0RC4 the problem now becomes:

TopologyException: EdgeRing::computePoints: found null Directed Edge

I believe there is in fact something wrong with the data.  However the
TopologyException does not identify the source of the problem.

In looking through the mailing list archives, I see questions around
this issue have come up in the past (eg September 2006).  I don't see
anyone suggesting ideas on how to find the offending data elements.

Also, trolling through google doesn't seem to turn up anything.

Does anyone have any ideas on how to explore the data to look for
problems such as this.

Thanks in advance!

On Thu, 2007-13-09 at 11:31 +0200, Andreas Laggner wrote:
> Hi Chris,
> 
> as i had this errors i installed postgis with GEOS 3.0, and such an 
> errors never occurs again! I am not sure, but postgis 1.3.1 can be built 
> with GEOS 2.2 too......just run the query select postgis_full_version(); 
> and check your version of GEOS.
> 
> cheers      Andreas
> 
> 
> Chris Hermansen schrieb:
> > Hi folks;
> >
> > I had this problem today:
> >
> > AssertionFailedException: EdgeRing::computePoints: found null Directed
> > Edge
> >
> > I see in the archives that there are others who have suffered this, back
> > in 2006 and then in 2005, but there don't seem to be any offerings of
> > techniques to either repair the code or the data - and based on the
> > error above, I'm not sure which is ultimately at fault.
> >
> > Does anyone have some more up-to-date thought on this?
> >
> > I'm running postgis-1.3.1 on Ubuntu with the packaged postgresql-8.2
> > installed.
> >
> > Thanks in advance!
> >   
> 
> 
-- 
Regards,

Chris Hermansen · mailto:clh at timberline.ca
tel:+1.604.714.2878 · fax:+1.604.733.0631
Timberline Natural Resource Group · http://www.timberline.ca
401 · 958 West 8th Avenue · Vancouver BC · Canada · V5Z 1E5

C'est ma façon de parler.