Grup fitur terkait dapat digabungkan menjadi FeatureCollection
, untuk
mengaktifkan operasi tambahan pada seluruh kumpulan seperti pemfilteran, pengurutan, dan rendering.
Selain fitur sederhana (geometri + properti), koleksi fitur juga dapat berisi koleksi lainnya.
Konstruktor FeatureCollection
Salah satu cara untuk membuat FeatureCollection
adalah dengan memberikan daftar fitur kepada
konstruktor. Fitur tidak harus memiliki jenis geometri atau properti yang sama. Contoh:
Editor Kode (JavaScript)
// Make a list of Features. var features = [ ee.Feature(ee.Geometry.Rectangle(30.01, 59.80, 30.59, 60.15), {name: 'Voronoi'}), ee.Feature(ee.Geometry.Point(-73.96, 40.781), {name: 'Thiessen'}), ee.Feature(ee.Geometry.Point(6.4806, 50.8012), {name: 'Dirichlet'}) ]; // Create a FeatureCollection from the list and print it. var fromList = ee.FeatureCollection(features); print(fromList);
import ee import geemap.core as geemap
Colab (Python)
# Make a list of Features. features = [ ee.Feature( ee.Geometry.Rectangle(30.01, 59.80, 30.59, 60.15), {'name': 'Voronoi'} ), ee.Feature(ee.Geometry.Point(-73.96, 40.781), {'name': 'Thiessen'}), ee.Feature(ee.Geometry.Point(6.4806, 50.8012), {'name': 'Dirichlet'}), ] # Create a FeatureCollection from the list and print it. from_list = ee.FeatureCollection(features) display(from_list)
Setiap geometri juga dapat diubah menjadi FeatureCollection
dari
hanya satu Feature
:
Editor Kode (JavaScript)
// Create a FeatureCollection from a single geometry and print it. var fromGeom = ee.FeatureCollection(ee.Geometry.Point(16.37, 48.225)); print(fromGeom);
import ee import geemap.core as geemap
Colab (Python)
# Create a FeatureCollection from a single geometry and print it. from_geom = ee.FeatureCollection(ee.Geometry.Point(16.37, 48.225)) display(from_geom)
Set Data Tabel
Earth Engine menghosting berbagai set data tabel. Untuk memuat set data tabel, berikan ID tabel ke konstruktor FeatureCollection
. Misalnya, untuk memuat data Ecoregion RESOLVE:
Editor Kode (JavaScript)
var fc = ee.FeatureCollection('RESOLVE/ECOREGIONS/2017'); Map.setCenter(12.17, 20.96, 3); Map.addLayer(fc, {}, 'ecoregions');
import ee import geemap.core as geemap
Colab (Python)
fc = ee.FeatureCollection('RESOLVE/ECOREGIONS/2017') m = geemap.Map() m.set_center(12.17, 20.96, 3) m.add_layer(fc, {}, 'ecoregions') display(m)
Perhatikan bahwa seperti set data gambar, Anda dapat menelusuri set data tabel di Katalog Data Earth Engine.
Sampel Acak
Untuk mendapatkan kumpulan titik acak di wilayah yang ditentukan, Anda dapat menggunakan:
Editor Kode (JavaScript)
// Define an arbitrary region in which to compute random points. var region = ee.Geometry.Rectangle(-119.224, 34.669, -99.536, 50.064); // Create 1000 random points in the region. var randomPoints = ee.FeatureCollection.randomPoints(region); // Display the points. Map.centerObject(randomPoints); Map.addLayer(randomPoints, {}, 'random points');
import ee import geemap.core as geemap
Colab (Python)
# Define an arbitrary region in which to compute random points. region = ee.Geometry.Rectangle(-119.224, 34.669, -99.536, 50.064) # Create 1000 random points in the region. random_points = ee.FeatureCollection.randomPoints(region) # Display the points. m = geemap.Map() m.center_object(random_points) m.add_layer(random_points, {}, 'random points') display(m)