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ee.ImageCollection.reduce
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Applies a reducer across all of the images in a collection.
If the reducer has a single input, it will be applied separately to each band of the collection; otherwise it must have the same number of inputs as the collection has bands.
The reducer output names determine the names of the output bands: reducers with multiple inputs will use the output names directly, while reducers with a single input will prefix the output name with the input band name (e.g., '10_mean', '20_mean').
| Usage | Returns | ImageCollection.reduce(reducer, parallelScale) | Image |
| Argument | Type | Details | this: collection | ImageCollection | The image collection to reduce. |
reducer | Reducer | The reducer to apply to the given collection. |
parallelScale | Float, default: 1 | A scaling factor used to limit memory use; using a larger parallelScale (e.g., 2 or 4) may enable computations that run out of memory with the default. |
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Last updated 2024-07-13 UTC.
[null,null,["Last updated 2024-07-13 UTC."],[[["\u003cp\u003eApplies a reducer function across all images within an ImageCollection, resulting in a single output Image.\u003c/p\u003e\n"],["\u003cp\u003eReducers can operate on individual bands or multiple bands simultaneously, determining the output band names accordingly.\u003c/p\u003e\n"],["\u003cp\u003eUtilizes a parallelScale factor to manage memory consumption during computation.\u003c/p\u003e\n"],["\u003cp\u003eAccess this functionality via the \u003ccode\u003eImageCollection.reduce()\u003c/code\u003e method, providing the reducer and optional parallelScale as parameters.\u003c/p\u003e\n"]]],[],null,["# ee.ImageCollection.reduce\n\nApplies a reducer across all of the images in a collection.\n\n\u003cbr /\u003e\n\nIf the reducer has a single input, it will be applied separately to each band of the collection; otherwise it must have the same number of inputs as the collection has bands.\n\nThe reducer output names determine the names of the output bands: reducers with multiple inputs will use the output names directly, while reducers with a single input will prefix the output name with the input band name (e.g., '10_mean', '20_mean').\n\n| Usage | Returns |\n|------------------------------------------------------|---------|\n| ImageCollection.reduce`(reducer, `*parallelScale*`)` | Image |\n\n| Argument | Type | Details |\n|--------------------|-------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------|\n| this: `collection` | ImageCollection | The image collection to reduce. |\n| `reducer` | Reducer | The reducer to apply to the given collection. |\n| `parallelScale` | Float, default: 1 | A scaling factor used to limit memory use; using a larger parallelScale (e.g., 2 or 4) may enable computations that run out of memory with the default. |"]]