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Returns the union of the two geometries.
Usage
Returns
BBox.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.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Missing the information I need","missingTheInformationINeed","thumb-down"],["Too complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2023-10-06 UTC."],[[["\u003cp\u003eReturns a Geometry representing the union of two geometries.\u003c/p\u003e\n"],["\u003cp\u003eAccepts a right operand Geometry, an optional maximum error margin, and an optional projection for the operation.\u003c/p\u003e\n"],["\u003cp\u003eCan be performed in a spherical coordinate system with distances in meters on the sphere if no projection is specified.\u003c/p\u003e\n"],["\u003cp\u003eIllustrated with JavaScript and Python examples demonstrating its usage with BBox geometries.\u003c/p\u003e\n"]]],["The `union` method combines two geometries, `left` and `right`, returning their union as a new `Geometry` object. It accepts optional `maxError` and `proj` arguments to control reprojection and error tolerance. `maxError` defines the maximum allowed error during reprojection. `proj` specifies the projection; if unspecified, it defaults to spherical coordinates with linear distances in meters. Example codes demonstrate combining bounding boxes using this method in JavaScript and Python.\n"],null,["# ee.Geometry.BBox.union\n\nReturns the union of the two geometries.\n\n\u003cbr /\u003e\n\n| Usage | Returns |\n|----------------------------------------------|----------|\n| BBox.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 BBox object.\nvar bBox = ee.Geometry.BBox(-122.09, 37.42, -122.08, 37.43);\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 BBox object.\nvar bBoxUnion = bBox.union({'right': inputGeom, 'maxError': 1});\n\n// Print the result to the console.\nprint('bBox.union(...) =', bBoxUnion);\n\n// Display relevant geometries on the map.\nMap.setCenter(-122.085, 37.422, 15);\nMap.addLayer(bBox,\n {'color': 'black'},\n 'Geometry [black]: bBox');\nMap.addLayer(inputGeom,\n {'color': 'blue'},\n 'Parameter [blue]: inputGeom');\nMap.addLayer(bBoxUnion,\n {'color': 'red'},\n 'Result [red]: bBox.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 BBox object.\nbbox = ee.Geometry.BBox(-122.09, 37.42, -122.08, 37.43)\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 BBox object.\nbbox_union = bbox.union(right=input_geom, maxError=1)\n\n# Print the result.\ndisplay('bbox.union(...) =', bbox_union)\n\n# Display relevant geometries on the map.\nm = geemap.Map()\nm.set_center(-122.085, 37.422, 15)\nm.add_layer(bbox, {'color': 'black'}, 'Geometry [black]: bbox')\nm.add_layer(input_geom, {'color': 'blue'}, 'Parameter [blue]: input_geom')\nm.add_layer(bbox_union, {'color': 'red'}, 'Result [red]: bbox.union')\nm\n```"]]