Franz's blog

Simplify or generalize polygons in ArcGIS

The generalization tools in ArcGIS allow information to refine or cleaning, in order to delete incorrect or unnecessary data, automating the identification of areas to intervene, resulting in obtaining more general information for examination.

For example, a polygon-type layer resulting from a slope map, vegetation, satellite imagery classified, scanned images, raster reclassified, etc., contain a large number of tiny areas that disturb the analysis of information, as shown in the following image.

Simplifying polygons in Arcmap

In this picture you can see a large number of polygons for surfaces with relatively insignificant population, as a first step to run clean, create a field and calculate the surface, then the attribute table in ascending order and select the polygons whose surface not be desirable for our work.

Select micro polygons in the attribute table in ArcMap

Then use the tool Eliminate within ArcToolbox.

ArcToolbox > Data Management Tools > Generalization > Eliminate

Eliminate tool in Arcgis

In Input Layer add Feature Class or Shapefile, assign the output directory and check the Eliminating polygon by border, this step can be performed as often as necessary to meet our goal.

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Small polygons eliminated

We now have a layer of refined polygons with greater reliability to run their analysis, in order to better aesthetics and remove the very geometric appearance shown between the edges of each category, you can smooth the polygons with the tool Smooth Polygon .

ArcToolbox > Data Management Tools > Generalization > Smooth Polygon

Smooth Polygon Arcgis

If you look at the options this tool we can establish tolerance to smooth polygons in the Smoothing Tolerance field, we tell ArcMap which we are the allowable length to smooth polygons, optionally check the Preserve endpoint for rings, and in the Handling topological errors field select FLAG_ERRORS to correct topological errors that may occur in the type polygon layer, using this toolkit will have a clearly noticeable result at first sight and free from erroneous data, the difference between first and last image of this post says it all.

Simplified polygons in Arcgis