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I am attempting to find the percentage of polygon features at a 5 meter resolution that are located inside each 25km raster cell. I am looking to assign percentages to each cell based on the percentage of a feature appearing in the cell (10%, 20%...).

Is there a tool that can do this procedure? The raster being limited to only a single value field has prevented me from being able to run attribute queries.

I am using ArcGIS

Thank you.

  • Which software are you using? ArcGIS, QGIS, MapInfo? – MDHald Jan 9 '14 at 16:33
  • I can't believe I forgot to add that. I am using ArcGIS – Dzinic Jan 9 '14 at 16:36
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Here's one of a few possible solutions in ArcGIS - the methodology is a bit involved, but it should solve your problem.

1) Use Create Fishnet (Data Management) (available at all license levels) to create a 25x25km grid of rectangular cells. This will have to be created concurrent to your raster (match the raster cells to the polygon grid cells) - you can do this using the *origin_coord* parameter.

2) Merge the fishnet with your polygon featureclass based on a common attribute - something such as a simple ID field will work.

3) Split the original polygon featureclass by the grid. Calculate the area of each piece of your original polygons.

4) You now have polygon pieces with an ID assigning to the the original whole polygon and the area of each. From this you can calculate the percentage of the whole polygon that each piece represents. This part may be a bit trickier to automate, but can be completed using the field calculator.

5) Merge the ID and percentage with the grid.

6) Convert the grid to a raster using the new percentage field.

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    Converting to vector for this operation is extremely inefficient. The whole thing can be done in one block stats operation. – whuber Jan 9 '14 at 17:54
  • @whuber Could you explain the block stats operation to me, please? I've never heard of that operation. – Dzinic Jan 9 '14 at 19:42
  • @whuber Thank you for the link. I am confused as to how this can analyse the vectorized data also. It seems to only take in the raster which does not contain the necessary values. – Dzinic Jan 10 '14 at 13:30
  • To what "vectorized data" are you referring? Your question does not mention any. – whuber Jan 10 '14 at 15:02

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