Hi Richard,

I've added a custom transformer to FMEpedia called a SelfIntersectorChecker
which just filters features that self-intersect - or not.  Let me know if it
doesn't work correctly on your dataset.

http://www.fmepedia.com/index.php/SelfIntersectorChecker

Best Regards,

Dan Iseminger
Safe Software


On 12/5/06, Dahlsten Nils-erik <[EMAIL PROTECTED]> wrote:

   Hi Richard.

Self-intersected objects leaving the SelfIntersector are always ketp
together as an aggregate (see the SelfIntersector documentation).
Use a Deaggregator after the SelfIntersector to split up the aggregates
into simple geometries.

Good luck.

/Nisse

 ------------------------------
*Från:* [email protected] [mailto:[EMAIL PROTECTED] *För *Richard
Wilkinson
*Skickat:* den 1 december 2006 16:05
*Till:* [email protected]
*Ämne:* RE: [fme] Re: Detecting Self Intersectsin a dataset

  Hi Mark,

I tried something very similar but it does not seem to catch the required
self intersects.

I have attached an example polygon for which the selfintersector transform
generates an _segment count of 1.  In this case a very simple self
intersect.  I have others that are more complex.  A few show _segment =2,
others =1, never more than 2.

The tracking from part of my workspace is

44     >     SelfIntersector     >    52    >     tester = 2      15 =
pass,   36 = fail

The numbers don't add up!  tester has 52 objects in, but only 51 out.

Richard Wilkinson






 -----Original Message-----
*From:* [email protected] [mailto:[EMAIL PROTECTED] *On Behalf Of *
mark2atsafe
*Sent:* 30 November 2006 17:33
*To:* [email protected]
*Subject:* [fme] Re: Detecting Self Intersectsin a dataset

 Hi Richard,
The SelfIntersector should add an attribute to the features telling
you how many pieces an element was split into. Therefore just use a
Tester to test for _segments > 1 and you'll have the intersecting
features.

With a unique ID (place a Counter before the SelfIntersector to create
one if necessary) you could use a LineJoiner to recreate the
intersecting features (set group-by = ID number)

Hope this helps

Mark

Mark Ireland, Senior Product Specialist
Safe Software Inc. Surrey, BC, CANADA
[EMAIL PROTECTED] <support%40safe.com> http://www.safe.com
Solutions for Spatial Data Translation, Distribution and Access

--- In [email protected] <fme%40yahoogroups.com>, "Richard Wilkinson"
<[EMAIL PROTECTED]> wrote:
>
> Hi,
>
> I want to provide a data creator with a list of self intersects in a
> dataset he is producing. I do not want to clean any problems found as
> some are quite complex and require data creator input to determine the
> correct geometry.
>
> I have experimented with the Selfintersector transform. I can see that
> I have 44 objects entering the selfintersector and 52 leaving it. But
> how can I list which 8 are selfintersecting?
>
> Can anyone suggest an approach for me to try.
>
> Thanks
>
> Richard Wilkinson
> Systems Analyst
> Resources - ICT Services
> Leicestershire County Council
> 0116 2657709
> [EMAIL PROTECTED]
>
>
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