AI-generated Key Takeaways
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Geometries can be visualized by adding them to the map using
Map.addLayer(). -
Printing a geometry provides information and metadata about it.
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Methods like
.area(),.perimeter(),.toGeoJSONString(),.type(),.coordinates(), and.geodesic()can access geometry information programmatically. -
By default, perimeter and area are returned in meters and square meters respectively, computed on the WGS84 spheroid.
Visualizing geometries
To visualize a geometry, add it to the map. For example:
Code Editor (JavaScript)
// Create a geodesic polygon. var polygon = ee . Geometry . Polygon ([ [[ - 5 , 40 ], [ 65 , 40 ], [ 65 , 60 ], [ - 5 , 60 ], [ - 5 , 60 ]] ]); // Create a planar polygon. var planarPolygon = ee . Geometry ( polygon , null , false ); // Display the polygons by adding them to the map. Map . centerObject ( polygon ); Map . addLayer ( polygon , { color : 'FF0000' }, 'geodesic polygon' ); Map . addLayer ( planarPolygon , { color : '000000' }, 'planar polygon' );
For more on visualizing, see Feature and FeatureCollection Visualization .
Geometry information and metadata
To view information about a geometry, print it. To access the information programmatically, Earth Engine provides several methods. For example, to get information about the polygon created previously, use:
Code Editor (JavaScript)
print ( 'Polygon printout: ' , polygon ); // Print polygon area in square kilometers. print ( 'Polygon area: ' , polygon . area (). divide ( 1000 * 1000 )); // Print polygon perimeter length in kilometers. print ( 'Polygon perimeter: ' , polygon . perimeter (). divide ( 1000 )); // Print the geometry as a GeoJSON string. print ( 'Polygon GeoJSON: ' , polygon . toGeoJSONString ()); // Print the GeoJSON 'type'. print ( 'Geometry type: ' , polygon . type ()); // Print the coordinates as lists. print ( 'Polygon coordinates: ' , polygon . coordinates ()); // Print whether the geometry is geodesic. print ( 'Geodesic? ' , polygon . geodesic ());
Observe that the perimeter (or length) of a geometry is returned in meters and the area is returned in square meters unless a projection is specified. By default, the computation is performed on the WGS84 spheroid and the result is computed in meters or square meters.
