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I would like to know how I can overlay a shapefile (A) into another gridded shapefile (B) and extract the information about which shapefile (A) polygons falls in each cells (B). And, more specifically, I would like to know how I can determine the percentage of each cell that are overlapped by a shapefile.

Shapefile A

Shapefile B

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Assuming you are using ArcMap:

  • Make sure that every square is a polygon feature with a unique ID number.
  • Perform a Union of the new clipped-grid.shp and the original polygons.
  • The resulting union.shp should tell you the ID of the original square that was clipped, and the name of the polygon that overlapped it.
  • Create a new column "Areas" and use Calculate Geometry to calculate the area of every feature.
  • Create a second column called "Percentage" and populate it using Field Calculator: [Percentage] = [Areas] / X * 100 (where x is the size of the original square.)
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    This answer is pretty much what I would do, but I'm not sure why the Clip operation is included. Theoretically it should definitely not be, since one may be wanting to know which cells are not overlapped at all by the polygons.
    – Chris W
    Feb 6 '15 at 21:50

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