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Clean Polygon Wizard

Ensures topological correctness of a polygon feature data set.

Inputs:

• A polygon feature layer
• Fuzzy tolerance

Outputs:

• New topologically correct Polygon feature class (no overlaps present)
  • Redundant data (overlaps and gaps smaller than the fuzzy tolerance) will be eliminated
  • The overlaps greater than the fuzzy tolerance are converted into new polygons.
  • Every new polygon carries the attributes of one of the source overlapping polygons
  • The attributes of the input data set are preserved
• Optional Point feature class that identifies the overlaps in the input data set. Several fields are added to the point attribute table enabling the user to identify the overlapping polygons in this location :
  • [Num_Over] - the number of overlapping polygons in this location.
  • [Old_FID1], [Old_FID2] ...[Old_FIDn] carrying the original IDs of the overlapping polygons

Notes :

• The default Fuzzy tolerance is calculated from the extents of the input layer using the formulae (W + H) / 2000000 where W and H are the with and height of the extent envelope.
• Larger values of the Fuzzy tolerance may be used to clean some bigger Gaps and Slivers, but it might lead to unwanted approximation of the input shapes. The better option is to use Fuzzy tolerance close to the default and then clean the remaining Gaps and Slivers with the "Clean Gaps Wizard" and 'Eliminate Wizard"
• A Fuzzy tolerance of  0 may be used if the original shapes have to be preserved exactly the same. In this case all the overlaps will be converted into new polygons.

Example:

Input Layer	After Clean
Detail A before Clean	Detail A after Clean

Attribute tables
Input table
Result table
Overlaps table