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Merges all geometries in a given collection into one and returns a collection containing a single feature with only an ID of 'union_result' and a geometry.
Usage
Returns
ImageCollection.union(maxError)
FeatureCollection
Argument
Type
Details
this: collection
FeatureCollection
The collection being merged.
maxError
ErrorMargin, default: null
The maximum error allowed when performing any necessary reprojections. If not specified, defaults to the error margin requested from the output.
[[["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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2023-10-06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\u003eCombines all geometries within a FeatureCollection into a single, unified geometry.\u003c/p\u003e\n"],["\u003cp\u003eReturns a new FeatureCollection containing one feature with the merged geometry, identified by 'union_result'.\u003c/p\u003e\n"],["\u003cp\u003eAccepts an optional \u003ccode\u003emaxError\u003c/code\u003e parameter to control the accuracy of reprojections during the merge process.\u003c/p\u003e\n"]]],[],null,["# ee.ImageCollection.union\n\nMerges all geometries in a given collection into one and returns a collection containing a single feature with only an ID of 'union_result' and a geometry.\n\n\u003cbr /\u003e\n\n| Usage | Returns |\n|---------------------------------------|-------------------|\n| ImageCollection.union`(`*maxError*`)` | FeatureCollection |\n\n| Argument | Type | Details |\n|--------------------|----------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------|\n| this: `collection` | FeatureCollection | The collection being merged. |\n| `maxError` | ErrorMargin, default: null | The maximum error allowed when performing any necessary reprojections. If not specified, defaults to the error margin requested from the output. |"]]