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Zonal Stats

October 29 2009 | 0 comments
Categories: Map Data

I have created a slope map with classes 0-3,3-5,5-50 deg. Overlay a polygon layer. How do I undertake zonal stats to calculate the percentage of each of the zonal classes in each unique polygon.

Mapping Center Answer:

You could do zonal stats--though I've always done vector based processing of that (not saying it's the only way, maybe somebody else will comment with some experience in the direction you're thinking of).

I convert the reclassified slope classes to polygons (though I also run a majority filter on them first to eliminate really small/insignificant holes--it's sort of like running Fill on your DEM). 

Then I would use the Split tool with your zone polygons, and finally dissolve based on Zone ID and slope class.

 

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