Step 1. Rasterize shapefile
Create a function that can determine whether a point at coordinates (x, y)
is or is not in the area. See here for more details on how to rasterize your shapefile into an array of the same dimensions as your target mask
def point_is_in_mask(mask, point):
# this is just pseudocode
return mask.contains(point)
Step 2. Create your mask
mask = np.zeros((height, width))
value = np.zeros((height, width))
for y in range(height):
for x in range(width):
if not point_is_in_mask(mask, (x, y)):
value[y][x] = np.nan