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[Rémi Cura <>]

A detail : 

all of this you could do in PostGIS.

Cheers,

Rémi-C

2013/12/4 Efi Fogel <>

What kernel are you using?

From your message it seems that you are not using an exact-predicate-exact-construction-kernel, as prescribed in the manual.

You must use an exact-predicate-exact-construction-kernel!

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On Wed, Dec 4, 2013 at 6:58 PM, <> wrote:

Hi!!
I have a problem with my project. Y work with maps (shapefiles) and I need to
divide some polygons (I use intersection and difference to obtain the
different parts) and then, I join this parts separately to another polygons.
The problem is that this join doesn't work fine. First, when it calculates an
important number of polygons, an exception is thrown (the polygons aren't
valid). If I see the visual representation, the boundary of the result has
some lines that should be cut, but they aren't.
I've found that the new vertex in the intersection of the lines doesn't belong
to the boundary, it's very very near, but not exactly in the boundary, I think
it's why the join function doesn't work.
Does anybody know how could I fix that problem, please? I've tried adding the
intersection point to the polygon but the result was even worse.
I can put some photos about the problem if it helps.
I know it's very abstract but I don't know what can I do to solve this
problem.
Thanks a lot in advance.

Regards.
Belén.

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