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ee.Geometry.union
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Returns the union of the two geometries.
Usage | Returns | Geometry.union(right, maxError, proj) | Geometry |
Argument | Type | Details | this: left | Geometry | The geometry used as the left operand of the operation. |
right | Geometry | The geometry used as the right operand of the operation. |
maxError | ErrorMargin, default: null | The maximum amount of error tolerated when performing any necessary reprojection. |
proj | Projection, default: null | The 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 Geometry object.
var geometry = ee.Geometry({
'type': 'Polygon',
'coordinates':
[[[-122.081, 37.417],
[-122.086, 37.421],
[-122.084, 37.418],
[-122.089, 37.416]]]
});
// Define other inputs.
var inputGeom = ee.Geometry.BBox(-122.085, 37.415, -122.075, 37.425);
// Apply the union method to the Geometry object.
var geometryUnion = geometry.union({'right': inputGeom, 'maxError': 1});
// Print the result to the console.
print('geometry.union(...) =', geometryUnion);
// Display relevant geometries on the map.
Map.setCenter(-122.085, 37.422, 15);
Map.addLayer(geometry,
{'color': 'black'},
'Geometry [black]: geometry');
Map.addLayer(inputGeom,
{'color': 'blue'},
'Parameter [blue]: inputGeom');
Map.addLayer(geometryUnion,
{'color': 'red'},
'Result [red]: geometry.union');
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)
# Define a Geometry object.
geometry = ee.Geometry({
'type': 'Polygon',
'coordinates': [[
[-122.081, 37.417],
[-122.086, 37.421],
[-122.084, 37.418],
[-122.089, 37.416],
]],
})
# Define other inputs.
input_geom = ee.Geometry.BBox(-122.085, 37.415, -122.075, 37.425)
# Apply the union method to the Geometry object.
geometry_union = geometry.union(right=input_geom, maxError=1)
# Print the result.
display('geometry.union(...) =', geometry_union)
# Display relevant geometries on the map.
m = geemap.Map()
m.set_center(-122.085, 37.422, 15)
m.add_layer(geometry, {'color': 'black'}, 'Geometry [black]: geometry')
m.add_layer(input_geom, {'color': 'blue'}, 'Parameter [blue]: input_geom')
m.add_layer(geometry_union, {'color': 'red'}, 'Result [red]: geometry.union')
m
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Last updated 2023-10-06 UTC.
[null,null,["Last updated 2023-10-06 UTC."],[[["\u003cp\u003eReturns a Geometry that represents the union of two input geometries.\u003c/p\u003e\n"],["\u003cp\u003eAccepts a right-hand Geometry operand, an optional error margin (\u003ccode\u003emaxError\u003c/code\u003e), and an optional projection (\u003ccode\u003eproj\u003c/code\u003e).\u003c/p\u003e\n"],["\u003cp\u003ePerforms the union operation, potentially reprojecting inputs if necessary, and returns the resulting combined Geometry.\u003c/p\u003e\n"],["\u003cp\u003eIf \u003ccode\u003eproj\u003c/code\u003e is not specified, the operation is performed in a spherical coordinate system using meters as the unit of distance.\u003c/p\u003e\n"]]],[],null,["# ee.Geometry.union\n\nReturns the union of the two geometries.\n\n\u003cbr /\u003e\n\n| Usage | Returns |\n|--------------------------------------------------|----------|\n| Geometry.union`(right, `*maxError* `, `*proj*`)` | Geometry |\n\n| Argument | Type | Details |\n|--------------|----------------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|\n| this: `left` | Geometry | The geometry used as the left operand of the operation. |\n| `right` | Geometry | The geometry used as the right operand of the operation. |\n| `maxError` | ErrorMargin, default: null | The maximum amount of error tolerated when performing any necessary reprojection. |\n| `proj` | Projection, default: null | The 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. |\n\nExamples\n--------\n\n### Code Editor (JavaScript)\n\n```javascript\n// Define a Geometry object.\nvar geometry = ee.Geometry({\n 'type': 'Polygon',\n 'coordinates':\n [[[-122.081, 37.417],\n [-122.086, 37.421],\n [-122.084, 37.418],\n [-122.089, 37.416]]]\n});\n\n// Define other inputs.\nvar inputGeom = ee.Geometry.BBox(-122.085, 37.415, -122.075, 37.425);\n\n// Apply the union method to the Geometry object.\nvar geometryUnion = geometry.union({'right': inputGeom, 'maxError': 1});\n\n// Print the result to the console.\nprint('geometry.union(...) =', geometryUnion);\n\n// Display relevant geometries on the map.\nMap.setCenter(-122.085, 37.422, 15);\nMap.addLayer(geometry,\n {'color': 'black'},\n 'Geometry [black]: geometry');\nMap.addLayer(inputGeom,\n {'color': 'blue'},\n 'Parameter [blue]: inputGeom');\nMap.addLayer(geometryUnion,\n {'color': 'red'},\n 'Result [red]: geometry.union');\n```\nPython setup\n\nSee the [Python Environment](/earth-engine/guides/python_install) page for information on the Python API and using\n`geemap` for interactive development. \n\n```python\nimport ee\nimport geemap.core as geemap\n```\n\n### Colab (Python)\n\n```python\n# Define a Geometry object.\ngeometry = ee.Geometry({\n 'type': 'Polygon',\n 'coordinates': [[\n [-122.081, 37.417],\n [-122.086, 37.421],\n [-122.084, 37.418],\n [-122.089, 37.416],\n ]],\n})\n\n# Define other inputs.\ninput_geom = ee.Geometry.BBox(-122.085, 37.415, -122.075, 37.425)\n\n# Apply the union method to the Geometry object.\ngeometry_union = geometry.union(right=input_geom, maxError=1)\n\n# Print the result.\ndisplay('geometry.union(...) =', geometry_union)\n\n# Display relevant geometries on the map.\nm = geemap.Map()\nm.set_center(-122.085, 37.422, 15)\nm.add_layer(geometry, {'color': 'black'}, 'Geometry [black]: geometry')\nm.add_layer(input_geom, {'color': 'blue'}, 'Parameter [blue]: input_geom')\nm.add_layer(geometry_union, {'color': 'red'}, 'Result [red]: geometry.union')\nm\n```"]]