[postgis-users] Preparing for Topology - St_CreateTopoGeo

[Sandro Santilli]

On Tue, Dec 06, 2011 at 08:33:53PM -0500, Chris English wrote:
> 
> In your experience, it there a method to predict where failuremight
> occur, or some characteristics of offending geometries...

Lines which are almost coincident but not quite.

> I was just wondering if through the multitudinous process of st_split,
> addface, addedgemodface,if a progression of small remainders from the
> splitting (or others) get carried forwardthat would fault st_createtopogeo
> as it gets around to updating {left,right}_face fields and the like.

The function performs noding as first thing so maybe you could do the
noding yourself on the whole data and see if it still creates problems.
If it does you could then select only the (noded) edges that intersect
a small buffer around the reported problematic point (was such problematic
point reported ?).

--strk;

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