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How do you get/extract the points that define a shapely polygon? Thanks!
Example of a shapely polygon
from shapely.geometry import Polygon # Create polygon from lists of points x = [list of x vals] y = [list of y vals] polygon = Polygon(x,y) 
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One of the simplest and most efficient ways of getting a list of points inside a polygon with Python is to rely on the Geopandas library and perform a spatial join. To do this, we simply create one geodataframe with points and another one with polygons, and join them with 'sjoin'.
Shapely is an offshoot of the GIS-Python project that provides spatial geometry functions independent of any geo-enabled database. In particular, it makes python point-in-polygon calculations very easy.
So, I discovered the trick is to use a combination of the Polygon class methods to achieve this.
If you want geodesic coordinates, you then need to transform these back to WGS84 (via pyproj, matplotlib's basemap, or something).
from shapely.geometry import Polygon #Create polygon from lists of points x = [list of x vals] y = [list of y vals] some_poly = Polygon(x,y) # Extract the point values that define the perimeter of the polygon x, y = some_poly.exterior.coords.xy If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
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