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ee.Geometry.Polygon.union

  • Theunion method returns the union of two geometries.

  • The method takes two required geometry inputs,left andright, and optionalmaxError andproj arguments.

  • The result of theunion method is a Geometry object.

 Returns the union of the two geometries.

UsageReturns
Polygon.union(right,maxError,proj)Geometry
ArgumentTypeDetails
this:leftGeometryThe geometry used as the left operand of the operation.
rightGeometryThe geometry used as the right operand of the operation.
maxErrorErrorMargin, default: nullThe maximum amount of error tolerated when performing any necessary reprojection.
projProjection, default: nullThe projection in which to perform the operation. If not specified, the operation will be performed in a spherical coordinate system, and linear distances will be in meters on the sphere.

Examples

Code Editor (JavaScript)

// Define a Polygon object.varpolygon=ee.Geometry.Polygon([[[-122.092,37.424],[-122.086,37.418],[-122.079,37.425],[-122.085,37.423]]]);// Define other inputs.varinputGeom=ee.Geometry.BBox(-122.085,37.415,-122.075,37.425);// Apply the union method to the Polygon object.varpolygonUnion=polygon.union({'right':inputGeom,'maxError':1});// Print the result to the console.print('polygon.union(...) =',polygonUnion);// Display relevant geometries on the map.Map.setCenter(-122.085,37.422,15);Map.addLayer(polygon,{'color':'black'},'Geometry [black]: polygon');Map.addLayer(inputGeom,{'color':'blue'},'Parameter [blue]: inputGeom');Map.addLayer(polygonUnion,{'color':'red'},'Result [red]: polygon.union');

Python setup

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

importeeimportgeemap.coreasgeemap

Colab (Python)

# Define a Polygon object.polygon=ee.Geometry.Polygon([[[-122.092,37.424],[-122.086,37.418],[-122.079,37.425],[-122.085,37.423],]])# Define other inputs.input_geom=ee.Geometry.BBox(-122.085,37.415,-122.075,37.425)# Apply the union method to the Polygon object.polygon_union=polygon.union(right=input_geom,maxError=1)# Print the result.display('polygon.union(...) =',polygon_union)# Display relevant geometries on the map.m=geemap.Map()m.set_center(-122.085,37.422,15)m.add_layer(polygon,{'color':'black'},'Geometry [black]: polygon')m.add_layer(input_geom,{'color':'blue'},'Parameter [blue]: input_geom')m.add_layer(polygon_union,{'color':'red'},'Result [red]: polygon.union')m

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Last updated 2023-10-06 UTC.