return geodesic area from spatial dataframe area property

DavidAnderson_1701 — Fri, 29 Apr 2022 14:29:52 GMT

Now that the calculate geomemtry tool in Pro gives the option to calculate either planar area or geodesic area, I was wondering if spatial data frames would have that option.

Currently data_frame.spatial.area returns planar area. The documentation (arcgis.features module — arcgis 2.0.0 documentation) does not show a option to flip between planar and geodesic.

Re: return geodesic area from spatial dataframe area property

HamishMorton — Fri, 29 Apr 2022 15:22:10 GMT

Hi @DavidAnderson_1701,

Have you thought about using the areas_and_lengths function of the geometry.functions class? It isnt as easy as accessing the area property by doesnt add too much additional overhead!

I have put together an example below:

from arcgis.gis import GIS from arcgis.geometry.functions import areas_and_lengths from arcgis.features import GeoAccessor from arcgis.geometry import LengthUnits, AreaUnits # Sign in gis = GIS("home") print(f"Signed in to {gis.url} as {gis.users.me.username}.\n\nCreating SEDF:") # Get Polygon layer and query to return SEDF polygon_flc = gis.content.get("<item_id>") print(f"Obtained item: {polygon_flc.title}") # Get layer polygon_fl = polygon_flc.layers[0] print(f"Obtained layer: {polygon_fl.properties.name}") # Query and return SEDF polygon_sdf = GeoAccessor.from_layer(polygon_fl) print(f"SEDF has {polygon_sdf.shape[0]} rows") # Get the area of the entire dataframe (planar) area_property_planar = polygon_sdf.spatial.area print(f"Area property (planar) is: {area_property_planar}") # Get the area of the entire dataframe (planar) areas_lengths_planar = areas_and_lengths( polygons=list(polygon_sdf["SHAPE"]), length_unit = LengthUnits.METER, area_unit = AreaUnits.SQUAREMETERS, calculation_type = "planar") print(f"Areas and lengths (planar) is: {sum(areas_lengths_planar['areas'])}") # Get the area of the entire dataframe (geodesic) areas_lengths_geodesic = areas_and_lengths( polygons=list(polygon_sdf["SHAPE"]), length_unit = LengthUnits.METER, area_unit = AreaUnits.SQUAREMETERS, calculation_type = "geodesic") print(f"Areas and lengths (geodesic) is: {sum(areas_lengths_geodesic['areas'])}")

Re: return geodesic area from spatial dataframe area property

DavidAnderson_1701 — Sat, 30 Apr 2022 15:21:42 GMT

That worked like a champ. I hadn't dug into the geometry module much before now. It is good to learn about the area_and_length functionality.

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return geodesic area from spatial dataframe area property

Re: return geodesic area from spatial dataframe area property

Re: return geodesic area from spatial dataframe area property