FeatureCollection filtern

Das Filtern einer FeatureCollection entspricht dem Filtern einer ImageCollection. Weitere Informationen finden Sie im Abschnitt Bildersammlungen filtern. Es gibt die Methoden featureCollection.filterDate() und featureCollection.filterBounds() sowie die Methode featureCollection.filter(), die mit allen ee.Filter verwendet werden kann. Beispiel:

Code-Editor (JavaScript)

// Load watersheds from a data table.
var sheds = ee.FeatureCollection('USGS/WBD/2017/HUC06')
  // Convert 'areasqkm' property from string to number.
  .map(function(feature){
    var num = ee.Number.parse(feature.get('areasqkm'));
    return feature.set('areasqkm', num);
  });

// Define a region roughly covering the continental US.
var continentalUS = ee.Geometry.Rectangle(-127.18, 19.39, -62.75, 51.29);

// Filter the table geographically: only watersheds in the continental US.
var filtered = sheds.filterBounds(continentalUS);

// Check the number of watersheds after filtering for location.
print('Count after filter:', filtered.size());

// Filter to get only larger continental US watersheds.
var largeSheds = filtered.filter(ee.Filter.gt('areasqkm', 25000));

// Check the number of watersheds after filtering for size and location.
print('Count after filtering by size:', largeSheds.size());

Python einrichten

Auf der Seite Python-Umgebung finden Sie Informationen zur Python API und zur Verwendung von geemap für die interaktive Entwicklung.

import ee
import geemap.core as geemap

Colab (Python)

# Load watersheds from a data table.
sheds = (
    ee.FeatureCollection('USGS/WBD/2017/HUC06')
    # Convert 'areasqkm' property from string to number.
    .map(
        lambda feature: feature.set(
            'areasqkm', ee.Number.parse(feature.get('areasqkm'))
        )
    )
)

# Define a region roughly covering the continental US.
continental_us = ee.Geometry.Rectangle(-127.18, 19.39, -62.75, 51.29)

# Filter the table geographically: only watersheds in the continental US.
filtered = sheds.filterBounds(continental_us)

# Check the number of watersheds after filtering for location.
display('Count after filter:', filtered.size())

# Filter to get only larger continental US watersheds.
large_sheds = filtered.filter(ee.Filter.gt('areasqkm', 25000))

# Check the number of watersheds after filtering for size and location.
display('Count after filtering by size:', large_sheds.size())