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#16
Charlie Frye

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Charlie - those things didn't help - tried both ELIMINATE and CHECK/REPAIR GEOMETRY.

But it did work in Workstation, using this workflow:
* Export to coverage from within ArcMap
* BUILD [coverage] arc
* In ArcEdit, one does an 'aselect' on arc with lpoly#/rpoly# = 1 (universe polygon)
* nselect
* put [new coverage]

And that's it!


Hugo was kind enough to send me his data and I reproduced the problem and didn't figure it out immediately, so I passed it along to the guys on the geoprocessing team.

So the problem was similar to what I originally thought--the vertexes in the original data do not quite coincide. On the Poland USSR border some were literally only a couple of millimeters apart. I was zooming in, but not far enough. I'm guessing the guys on the geoprocessing team converted the FEATURE VERTICES TO POINT and then verified the coordinates.

My regret is forgetting the name of, and entirely about, the command that fixes that. In Desktop we have a tool called INTEGRATE. I processed Hugo's features with a 5m tolerance and then ran POLYGON TO LINE and it worked like a champ.

So, there really isn't a need to go back to Workstation for that issue.
Charlie Frye
Chief Cartographer
Software Products Department
ESRI, Redlands, California

#17
frax

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Cool Charlie - thanks! I'll remember that.

(Not that I don't mind going back to workstation - I find a lot of operations quite convenient there...)

:)
Hugo Ahlenius
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#18
A. Fenix

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hello all,

i'm still curious why the "eliminate" tool didn't take care of those small slivers in the shapefile, and thus immediately resolve those little errors in topology...

any answers out there?

analisa
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#19
Charlie Frye

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i'm still curious why the "eliminate" tool didn't take care of those small slivers in the shapefile, and thus immediately resolve those little errors in topology...

any answers out there?


Eliminate is designed to deal with "sliver" polygons--Hugo's data just had "sliver" gaps.

Let's say Hugo's gaps were polygons, as long as none of the slivers were actually larger than a country, they could've been queried for (based on having a small area) and then eliminate would have worked.

Eliminate can also be used as a specialized case by case aggregator--i.e., when two types of features share an edge and it's your intention to merge the smaller features of type A into the larger features of type B (versus types C-F). The Aggregate command, requires a non-zero aggregation distance parameter which allows polygons that do not actually touch to get aggregated.
Charlie Frye
Chief Cartographer
Software Products Department
ESRI, Redlands, California




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