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ee.Geometry.MultiPolygon.union
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Returns the union of the two geometries.
| Usage | Returns | MultiPolygon.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 MultiPolygon object.
var multiPolygon = ee.Geometry.MultiPolygon(
[[[[-122.092, 37.424],
[-122.086, 37.418],
[-122.079, 37.425],
[-122.085, 37.423]]],
[[[-122.081, 37.417],
[-122.086, 37.421],
[-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 MultiPolygon object.
var multiPolygonUnion = multiPolygon.union({'right': inputGeom, 'maxError': 1});
// Print the result to the console.
print('multiPolygon.union(...) =', multiPolygonUnion);
// Display relevant geometries on the map.
Map.setCenter(-122.085, 37.422, 15);
Map.addLayer(multiPolygon,
{'color': 'black'},
'Geometry [black]: multiPolygon');
Map.addLayer(inputGeom,
{'color': 'blue'},
'Parameter [blue]: inputGeom');
Map.addLayer(multiPolygonUnion,
{'color': 'red'},
'Result [red]: multiPolygon.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 MultiPolygon object.
multipolygon = ee.Geometry.MultiPolygon([
[[
[-122.092, 37.424],
[-122.086, 37.418],
[-122.079, 37.425],
[-122.085, 37.423],
]],
[[[-122.081, 37.417], [-122.086, 37.421], [-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 MultiPolygon object.
multipolygon_union = multipolygon.union(right=input_geom, maxError=1)
# Print the result.
display('multipolygon.union(...) =', multipolygon_union)
# Display relevant geometries on the map.
m = geemap.Map()
m.set_center(-122.085, 37.422, 15)
m.add_layer(
multipolygon, {'color': 'black'}, 'Geometry [black]: multipolygon'
)
m.add_layer(input_geom, {'color': 'blue'}, 'Parameter [blue]: input_geom')
m.add_layer(
multipolygon_union, {'color': 'red'}, 'Result [red]: multipolygon.union'
)
m
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Last updated 2023-10-06 UTC.
[null,null,["Last updated 2023-10-06 UTC."],[[["\u003cp\u003eThe \u003ccode\u003eunion\u003c/code\u003e method returns a Geometry representing the union of two geometries.\u003c/p\u003e\n"],["\u003cp\u003eIt takes a \u003ccode\u003eright\u003c/code\u003e geometry as input, along with optional \u003ccode\u003emaxError\u003c/code\u003e and \u003ccode\u003eproj\u003c/code\u003e parameters for error handling and projection, respectively.\u003c/p\u003e\n"],["\u003cp\u003eThe union operation combines the spatial extent of the input geometries into a single output geometry.\u003c/p\u003e\n"],["\u003cp\u003eThis method can be applied to MultiPolygon objects, as demonstrated in the examples provided for JavaScript and Python.\u003c/p\u003e\n"]]],["The `union` method combines two geometries, a `left` and a `right`, into a single geometry representing their union. Optional parameters include `maxError`, which sets the tolerated error during reprojection, and `proj`, the operation's projection. The method returns a new geometry. Example shows creating a `MultiPolygon` object, a `BBox` geometry, and combining them with a `union` call, the result then being printed and displayed on a map.\n"],null,["# ee.Geometry.MultiPolygon.union\n\nReturns the union of the two geometries.\n\n\u003cbr /\u003e\n\n| Usage | Returns |\n|------------------------------------------------------|----------|\n| MultiPolygon.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 MultiPolygon object.\nvar multiPolygon = ee.Geometry.MultiPolygon(\n [[[[-122.092, 37.424],\n [-122.086, 37.418],\n [-122.079, 37.425],\n [-122.085, 37.423]]],\n [[[-122.081, 37.417],\n [-122.086, 37.421],\n [-122.089, 37.416]]]]);\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 MultiPolygon object.\nvar multiPolygonUnion = multiPolygon.union({'right': inputGeom, 'maxError': 1});\n\n// Print the result to the console.\nprint('multiPolygon.union(...) =', multiPolygonUnion);\n\n// Display relevant geometries on the map.\nMap.setCenter(-122.085, 37.422, 15);\nMap.addLayer(multiPolygon,\n {'color': 'black'},\n 'Geometry [black]: multiPolygon');\nMap.addLayer(inputGeom,\n {'color': 'blue'},\n 'Parameter [blue]: inputGeom');\nMap.addLayer(multiPolygonUnion,\n {'color': 'red'},\n 'Result [red]: multiPolygon.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 MultiPolygon object.\nmultipolygon = ee.Geometry.MultiPolygon([\n [[\n [-122.092, 37.424],\n [-122.086, 37.418],\n [-122.079, 37.425],\n [-122.085, 37.423],\n ]],\n [[[-122.081, 37.417], [-122.086, 37.421], [-122.089, 37.416]]],\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 MultiPolygon object.\nmultipolygon_union = multipolygon.union(right=input_geom, maxError=1)\n\n# Print the result.\ndisplay('multipolygon.union(...) =', multipolygon_union)\n\n# Display relevant geometries on the map.\nm = geemap.Map()\nm.set_center(-122.085, 37.422, 15)\nm.add_layer(\n multipolygon, {'color': 'black'}, 'Geometry [black]: multipolygon'\n)\nm.add_layer(input_geom, {'color': 'blue'}, 'Parameter [blue]: input_geom')\nm.add_layer(\n multipolygon_union, {'color': 'red'}, 'Result [red]: multipolygon.union'\n)\nm\n```"]]