Geometri Shapely dan relasi spasial

Bekerja dengan Data Geospasial di Python

Dani Arribas-Bel

Geographic Data Science Lab (University of Liverpool)

Nilai geometri skalar

cities = geopandas.read_file("ne_110m_populated_places.shp")
cities.head()

           name                                      geometry
0  Vatican City   POINT (12.45338654497177 41.90328217996012)
1    San Marino     POINT (12.44177015780014 43.936095834768)
2         Vaduz   POINT (9.516669472907267 47.13372377429357)
3       Lobamba  POINT (31.19999710971274 -26.46666746135247)
4    Luxembourg   POINT (6.130002806227083 49.61166037912108)

brussels = cities.loc[170, 'geometry']
print(brussels)

POINT (4.33137074969045 50.83526293533032)

Nilai geometri skalar

brussels = cities.loc[170, 'geometry']
print(brussels)

POINT (4.33137074969045 50.83526293533032)

type(brussels)

shapely.geometry.point.Point

Paket Python Shapely

type(brussels)

shapely.geometry.point.Point

Shapely

Paket Python untuk manipulasi dan analisis objek geometri
Menyediakan objek Point, LineString, dan Polygon
GeoSeries (kolom 'geometry' pada GeoDataFrame) berisi objek Shapely

Objek geometri

Mengambil dari GeoDataFrame:

brussels = cities.loc[170, 'geometry']
paris = cities.loc[235, 'geometry']
belgium = countries.loc[countries['name'] == 'Belgium', 'geometry'].squeeze()
france = countries.loc[countries['name'] == 'France', 'geometry'].squeeze()
uk = countries.loc[countries['name'] == 'United Kingdom', 'geometry'].squeeze()

Membuat manual:

from shapely.geometry import Point
p = Point(1, 2)
print(p)

POINT (1 2)

Metode spasial

Luas suatu geometri:

belgium.area

3.8299974609075753

Jarak antara 2 geometri:

brussels.distance(paris)

2.8049127723186214

Dan banyak lagi! (mis. centroid, simplify, ...)

Relasi spasial

geopandas.GeoSeries([belgium, france, uk, paris,  brussels, line]).plot()

Relasi spasial

belgium.contains(brussels)

True

france.contains(brussels)

False

brussels.within(belgium)

True

belgium.touches(france)

True

line.intersects(france)

True

line.intersects(uk)

False

Ayo berlatih!

Bekerja dengan Data Geospasial di Python