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The cell size is not used to allow adjustment. You have to manually adjust the resolution of the coarser raster to make it match the finer raster (or set the Cell size raster analysis environment to Minimum of Inputs). https://desktop.arcgis.com/en/desktop/latest/tools/spatial-analyst-toolbox/h-working-with-tabulate-area.htm "Some of the area values in ...


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From Wikipedia: For a general sphere of radius r, any portion of its surface with area A = r2 subtends one steradian. So you can multiply your steradians value by r2 to get the area value. Using r = 6371 km: 8.101249039703731e-8 * (6371 * 6371) = 3.288 km²


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Here’s my solution. I gave up with ArcGIS and QGIS, instead opting to output the data to file and perform the calculation in R. # Load library library(raster) # Load chlorophyll data chloro <- raster("../data/chloro.tif") # Load polygons poly <- shapefile("../data/poly.shp") # Extract data in polygons poly.chloro <- extract(chloro, poly) # ...


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There are a couple of ways of tackling this problem. The first is to try and find a tool to do the job. The second is to use a bit of Python scripting to do it manually. Since finding tools seems to be hard, here's a python solution. You'll need to figure out how to install python/gdal/numpy yourself, but once you do you won't be disappointed. It's ...


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To do this I would use two tools: Intersect (Analysis): Computes a geometric intersection of the input features. Features or portions of features which overlap in all layers and/or feature classes will be written to the output feature class. then Summary Statistics (Analysis) Calculates summary statistics for field(s) in a table.


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Could you calculate quintiles for the raster within each polygon and use these values to create contour lines where the lower quintile represents the 80/20 boundary?


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I would convert the polygon layer into a raster data set with feature to raster tool and then do a raster overlay analysis using raster calculator. Make sure you are using the same projection and coordinate systems for both or your results will be wrong. Good luck!


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In your example, the population value of the county is irrelevant to the question (it would have to be something like percentage of people in county Y who read Magazine X). The county borders simply serve as boundaries for aggregating the zip code values. However, if the issue is that zip code polys cross the boundary of a county and you only want the ...


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Without precisely knowing the projection of your data, it's difficult to be sure what went wrong with your calculation. That said, it's always risky methodology to allow any kind of reprojection on the fly in your GIS when you're additionally performing geometry calculations. The same is true if you have several layers in a mixture of projections, in which ...


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The $area works well. The problem seems restricted to the identify tool. Gonna report this as a QGIS bug.


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This is commonly referred to as feature detection. There are many software packages that have libraries for feature detection/extraction. To name a few: Python (Scikit-image): Template Matching Blob Detection Matlab: Feature Detection and Extraction


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As I understand it, according to the Google Maps/Earth Additional Terms of Service you cant't as this would be considered "derivative works of the Content". "Unless you have received prior written authorization from Google (or, as applicable, from the provider of particular Content), you must not: (a) copy, translate, modify, or make derivative works of the ...


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Sorry, but the layers are not in the same CRS. The Catchments is in an Albers Equal area projection (units-meters) and the other two are in Haartebeesthoek94, with degree as units. So your area calculations are in square degrees. If you reproject the transmissivity and intersect polygons to Albers Eq Area (with the "Save As..." option in QGIS) then ...



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