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#1
Robert2009

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I have a question for someone out there who has similiar situation as I am in. This co-worker worked on digitized line work/polyline in a 7.5 quad and he smooth all the lines within the quad. He hand it to me as a polygon with topology. The topology is 0.001 in a personal geodatabase.

I review the polygon for QA/QC proeducre and found that the layer has numerous of smaller polygons. I was thinking it was because of the way of the vertices and the topology builds and cause it to generate many smaller polygons in between the vertices. How do I correct this problem?

For example, you have a data that has 10 polygons before you run topology. Then after the topology, you have the same data but it built 100's of polygons. Even though, you looked at the data it looks like it has 10 polygons. When you zoom in and you found lots of smaller polygons .

Do I make myself clearly to you ? Let me know if you have the same situation as I am I would like to solve this problem.

Thanks !

#2
dsl

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I'm assuming you are using a version of ArcGIS with at least an ArcEditor license. How are you creating topology? If you are using geodatabase topology to check for errors, then it should create a separate layer with just the errors. It's possible when your coworker smoothed the polygons, the shared boundaries became overlapping boundaries, or when this person was digitizing they did not correctly digitize shared boundaries and just digitized them as separate polygons (e.g. no snapping, or tracing, or other tools ArcGIS has to maintain correct topology).

Cheers,
David

#3
Dustin Edge

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Hi Robert

As dsl mentioned, the 100s of polygons are topology errors. You can use the Error Inspector on the Topology Toolbar alongwith the other topology edit tools to go through the list and choose how to fix them.
For example: merge a small error polygon with it's larger neighbour or fill in a gap between 2 polygons....

Your starting point will be the topology error layer....

Cleaning up other people's shoddy digitising is never fun...been there too many times.

Cheers
Kind Regards,

Dustin


Dustin Edge
Snr GIS Analyst
AECOM Australia




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