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The problem was that the zones did not have unique id's. When I calculated the id field, it was not set to a large enough precision for all of the polygons. I recreated the id field with a larger precision and problem solved. Thanks!!


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There is an internal conversion of the polygons to raster when you process a tabulate area (same with zonal histogram and zonal statistics). Therefore even if your polygons align with the raster cells, you could have a feature to raster conversion that ends up with non matching grids. This can be fixed by setting the tool environment with equal pixel size ...


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If you don't want to use an equal-area reprojection, you might get acceptable accuracy by calculating an approximation with the field calculator. It will calculate polygon areas as DecimalDegrees^2 with the $area field, but you would need to correct it for the decreasing scale of the longitudinal measurements. Entering an expression of: ...


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I am not sure how much are you familial with R, but I think there is the best and very simple solution of your problem: library(raster) # read "raster" library setwd("D:/Data/....") # set you working directory r<-raster("your_raster.tif") # import your category raster file t<-freq(r) # ...


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Although you are dealing with an image and not a polygon layer for your land use classifications, a Planning Department would normally have this layer in a polygon format for future planned land uses. My County has such a layer available for download. If you had a Polygon land use layer, you can set up the symbology labels of your layer to show area using ...


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1. Tabulate areas The more robust method of calculating areas is to use the Tabulate Areas geoprocessing tool within Spatial Analyst. This is intended to calculate a breakdown of areas for classified raster data for a series of zones. For example, if you need the area of each land cover class for each city or town within your study area. To get the total ...


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If not done already, calculate the area in a field for your polygons Create centroids. Area field should carry over to the points. Create and calculate a radius field that corresponds to a circle of the given area, for each point. The formula for circle area is A = pi*r^2, so r = Sqr(A/pi). Pi = 4*Atn(1). The exact VBScript field calculation is: Sqr ( ...


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It looks like your coordinates are longitude and latitude, yes? Use Shapely's shapely.ops.transform function to transform the polygon to projected equal area coordinates and then take the area. python geom_aea = transform( partial( pyproj.transform, pyproj.Proj(init='EPSG:4326'), pyproj.Proj( proj='aea', lat1=geom.bounds[1], ...



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