Extract points/coordinates from a polygon in Shapely
polygon, python, shapely
Solution
The trick is to use a combination of the `Polygon` class methods:
from shapely.geometry import Polygon
# Create polygon from lists of points
x = [0.0, 0.0, 1.0, 1.0, 0.0]
y = [0.0, 1.0, 1.0, 0.0, 0.0]
poly = Polygon(zip(x,y))
# Extract the point values that define the perimeter of the polygon
xx, yy = poly.exterior.coords.xy
# Note above return values are of type `array.array`
assert x == xx.tolist()
assert y == yy.tolist()
If you would like them as coordinate pairs
assert tuple(poly.exterior.coords) == tuple(zip(x,y))
or as a `numpy` array
assert np.array_equal(np.array(poly.exterior.coords), np.asarray(tuple(zip(x,y))))
Problem
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) ```