PyGEOS seems to return None instead of MultiLineString in pygeos.boundary if you pass MultiPolygon in.
import geopandas as gpd
import pygeos
df = gpd.read_file(gpd.datasets.get_path('nybb')) # MultiPolygon geometry
pygeos.boundary(df.geometry.values.data)
-> array([None, None, None, None, None], dtype=object)While shapely returns expected MultiLineString.
df.geometry.iloc[0].boundary.type
-> 'MultiLineString'
PyGEOS seems to return
Noneinstead of MultiLineString inpygeos.boundaryif you pass MultiPolygon in.While shapely returns expected MultiLineString.