Feature Overview

    A Feature in Earth Engine is defined as a GeoJSON Feature. Specifically, a Feature is an object with a geometry property storing a Geometry object (or null) and a properties property storing a dictionary of other properties.

    Creating Feature objects

    To create a Feature , provide the constructor with a Geometry and (optionally) a dictionary of other properties. For example:

    Code Editor (JavaScript) 

     // Create an ee.Geometry. 
 var 
  
 polygon 
  
 = 
  
 ee 
 . 
 Geometry 
 . 
 Polygon 
 ([ 
  
 [[ 
 - 
 35 
 , 
  
 - 
 10 
 ], 
  
 [ 
 35 
 , 
  
 - 
 10 
 ], 
  
 [ 
 35 
 , 
  
 10 
 ], 
  
 [ 
 - 
 35 
 , 
  
 10 
 ], 
  
 [ 
 - 
 35 
 , 
  
 - 
 10 
 ]] 
 ]); 
 // Create a Feature from the Geometry. 
 var 
  
 polyFeature 
  
 = 
  
 ee 
 . 
 Feature 
 ( 
 polygon 
 , 
  
 { 
 foo 
 : 
  
 42 
 , 
  
 bar 
 : 
  
 'tart' 
 });

    Python setup

    See the Python Environment page for information on the Python API and using geemap for interactive development.

     import 
  
 ee 
 import 
  
 geemap.core 
  
 as 
  
 geemap

    Colab (Python) 

     # Create an ee.Geometry. 
 polygon 
 = 
 ee 
 . 
 Geometry 
 . 
 Polygon 
 ( 
 [[[ 
 - 
 35 
 , 
 - 
 10 
 ], 
 [ 
 35 
 , 
 - 
 10 
 ], 
 [ 
 35 
 , 
 10 
 ], 
 [ 
 - 
 35 
 , 
 10 
 ], 
 [ 
 - 
 35 
 , 
 - 
 10 
 ]]] 
 ) 
 # Create a Feature from the Geometry. 
 poly_feature 
 = 
 ee 
 . 
 Feature 
 ( 
 polygon 
 , 
 { 
 'foo' 
 : 
 42 
 , 
 'bar' 
 : 
 'tart' 
 })

    As with a Geometry , a Feature may be printed or added to the map for inspection and visualization:

    Code Editor (JavaScript) 

     print 
 ( 
 polyFeature 
 ); 
 Map 
 . 
 addLayer 
 ( 
 polyFeature 
 , 
  
 {}, 
  
 'feature' 
 );

    Python setup

    See the Python Environment page for information on the Python API and using geemap for interactive development.

     import 
  
 ee 
 import 
  
 geemap.core 
  
 as 
  
 geemap

    Colab (Python) 

     display 
 ( 
 poly_feature 
 ) 
 m 
 = 
 geemap 
 . 
 Map 
 () 
 m 
 . 
 add_layer 
 ( 
 poly_feature 
 , 
 {}, 
 'feature' 
 ) 
 display 
 ( 
 m 
 )

    A Feature need not have a Geometry and may simply wrap a dictionary of properties. For example:

    Code Editor (JavaScript) 

     // Create a dictionary of properties, some of which may be computed values. 
 var 
  
 dict 
  
 = 
  
 { 
 foo 
 : 
  
 ee 
 . 
 Number 
 ( 
 8 
 ). 
 add 
 ( 
 88 
 ), 
  
 bar 
 : 
  
 'nihao' 
 }; 
 // Create a null geometry feature with the dictionary of properties. 
 var 
  
 nowhereFeature 
  
 = 
  
 ee 
 . 
 Feature 
 ( 
 null 
 , 
  
 dict 
 );

    Python setup

    See the Python Environment page for information on the Python API and using geemap for interactive development.

     import 
  
 ee 
 import 
  
 geemap.core 
  
 as 
  
 geemap

    Colab (Python) 

     # Create a dictionary of properties, some of which may be computed values. 
 dic 
 = 
 { 
 'foo' 
 : 
 ee 
 . 
 Number 
 ( 
 8 
 ) 
 . 
 add 
 ( 
 88 
 ), 
 'bar' 
 : 
 'nihao' 
 } 
 # Create a null geometry feature with the dictionary of properties. 
 nowhere_feature 
 = 
 ee 
 . 
 Feature 
 ( 
 None 
 , 
 dic 
 )

    In this example, note that the dictionary supplied to the Feature contains a computed value. Creating features in this manner is useful for exporting long-running computations with a Dictionary result (e.g. image.reduceRegion() ). See the FeatureCollections and Importing Table Data or Exporting guides for details.

    Each Feature has one primary Geometry stored in the geometry property. Additional geometries may be stored in other properties. Geometry methods such as intersection and buffer also exist on Feature as a convenience for getting the primary Geometry , applying the operation, and setting the result as the new primary Geometry . The result will retain all the other properties of the Feature on which the method is called. There are also methods for getting and setting the non-geometry properties of the Feature . For example:

    Code Editor (JavaScript) 

     // Make a feature and set some properties. 
 var 
  
 feature 
  
 = 
  
 ee 
 . 
 Feature 
 ( 
 ee 
 . 
 Geometry 
 . 
 Point 
 ([ 
 - 
 122.22599 
 , 
  
 37.17605 
 ])) 
  
 . 
 set 
 ( 
 'genus' 
 , 
  
 'Sequoia' 
 ). 
 set 
 ( 
 'species' 
 , 
  
 'sempervirens' 
 ); 
 // Get a property from the feature. 
 var 
  
 species 
  
 = 
  
 feature 
 . 
 get 
 ( 
 'species' 
 ); 
 print 
 ( 
 species 
 ); 
 // Set a new property. 
 feature 
  
 = 
  
 feature 
 . 
 set 
 ( 
 'presence' 
 , 
  
 1 
 ); 
 // Overwrite the old properties with a new dictionary. 
 var 
  
 newDict 
  
 = 
  
 { 
 genus 
 : 
  
 'Brachyramphus' 
 , 
  
 species 
 : 
  
 'marmoratus' 
 }; 
 var 
  
 feature 
  
 = 
  
 feature 
 . 
 set 
 ( 
 newDict 
 ); 
 // Check the result. 
 print 
 ( 
 feature 
 );

    Python setup

    See the Python Environment page for information on the Python API and using geemap for interactive development.

     import 
  
 ee 
 import 
  
 geemap.core 
  
 as 
  
 geemap

    Colab (Python) 

     # Make a feature and set some properties. 
 feature 
 = 
 ( 
 ee 
 . 
 Feature 
 ( 
 ee 
 . 
 Geometry 
 . 
 Point 
 ([ 
 - 
 122.22599 
 , 
 37.17605 
 ])) 
 . 
 set 
 ( 
 'genus' 
 , 
 'Sequoia' 
 ) 
 . 
 set 
 ( 
 'species' 
 , 
 'sempervirens' 
 ) 
 ) 
 # Get a property from the feature. 
 species 
 = 
 feature 
 . 
 get 
 ( 
 'species' 
 ) 
 display 
 ( 
 species 
 ) 
 # Set a new property. 
 feature 
 = 
 feature 
 . 
 set 
 ( 
 'presence' 
 , 
 1 
 ) 
 # Overwrite the old properties with a new dictionary. 
 new_dic 
 = 
 { 
 'genus' 
 : 
 'Brachyramphus' 
 , 
 'species' 
 : 
 'marmoratus' 
 } 
 feature 
 = 
 feature 
 . 
 set 
 ( 
 new_dic 
 ) 
 # Check the result. 
 display 
 ( 
 feature 
 )

    In the previous example, note that properties can be set with either a key-value pair, or with a dictionary. Also note that feature.set() overwrites existing properties.
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