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After merging a set of shapefiles I've ended up with polygons that have vertices and lines within them. Is there a simple tool to remove these vertices and clean the polygon in ArcMap 10.2?

I realise the same question has been asked here, but it does not state the GIS-program and I cannot find the tool mentioned in the answer (delete ring in the advanced digitising toolbar).

EDIT: when zooming in very far, the lines and dots appear to be tiny triangles. They are not separate features, but holes in the polygons that arose from merging polygons that had not been lined up nicely. I am now looking for a way to repair there holes.

I reckon there is a simple tool to do this, but I cannot seem to find it.

example_slivers example_hole

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    The tool that is referenced in the question that you reference is in the QGIS program – Zachary Nov 18 '14 at 14:29
  • How many polygons do you have? A quick if inelegant method I've used in ArcMap is to draw a large rectangle with the select tool to select one or more features, then holding the shift key click on the polygons I want to keep to deselect them, then click on the edit vertices tool, and then use the remove vertices tool to draw a large square(s) to delete all the vertices within that make up your holes. Use a copy or have a backup of course just in case. – johns Nov 18 '14 at 18:23
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You can use the Select (Analysis) tool to select a subset of features based on a SQL expression and export the selected results to a new feature class. In this case, I used the following expression:

SHAPE_Area > 100

Alternatively, you can perform the same action directly on the attributes using the following workflow:

  1. Open attribute table > Select by Attributes > SHAPE_Area > 100
  2. Right-click layer in table of contents > Data > Export Data...
  3. Export selected features

enter image description here

  • Seems handy, but I do not want to extract a certain set of features, but a set of lines and points that are part of the feature that should not be there. – Renée Nov 18 '14 at 14:48
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    A polygon shapefile can only have polygons--points and lines are not allowed. The approach I highlighted selects the polygons you want and creates a new shapefile based on that (disregarding all of the slivers/small polygons). Sounds like you may need to use "Check/Repair Geometry" if you have broken geometry. Otherwise, the "Eliminate" tool may work for you by merging the small polygons with larger polygons. – Aaron Nov 18 '14 at 14:57
  • You are right, when I zoom in very far, I can see that lines are made up of very narrow triangles. I think they originate from the original polygons that were merged - the edges must have not lined up nicely... Still, I am not deleting separate features, but tiny holes in a larger polygon. – Renée Nov 18 '14 at 15:17
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    @Renée Then you will want to use the Eliminate tool: resources.arcgis.com/en/help/main/10.2/index.html#//… – Aaron Nov 18 '14 at 15:23
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    I found multiple ways to solve the problem: the tool 'eliminate polygon parts' in ArcInfo and 'clean donut holes' in ET Geowizards. – Renée Nov 18 '14 at 16:13
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In order to solve your problem:

  1. Create a FileGeodatabase
  2. In the FileGeodatabase create a FeatureDataset
  3. Import the shape in the FeatureDataset
  4. In the FeatureDataset create a Topology
  5. In the wizard choose next and in the Rules page click Add Rule
  6. Select "Must Not Overlap" or "Must Not Have Gaps", check "Show Errors" and click OK.
  7. Complete the wizard and validate the topology.
  8. Open the topolgy in ArcMap, you can see the errors
  9. Start editing and open the Topology toolbar
  10. On the Topolgy toolbar click on "Error Inspector"

At this time you can edit the feature class to remove errors.

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Using the Area of the polygon only works if you don't have multipart polygons or after exploding multipart polygons and it doesn't fill holes in the polygon, if I'm not mistaken. Have you tried using "Eliminate polygon parts" in ArcGIS (Data Management Toolbox - Generalization)

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If you're just trying to do one or two manually, this solution worked for me.

Make sure you are in an active edit session, highlight the feature you want to edit, and look for the "edit vertices" toolbar. Select the "delete vertex" button, draw a box around the gaps, and then press delete.

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