Announcement: All noncommercial projects registered to use Earth Engine before
April 15, 2025 must
verify noncommercial eligibility to maintain Earth Engine access.
ee.ImageCollection.reduceColumns
Stay organized with collections
Save and categorize content based on your preferences.
Apply a reducer to each element of a collection, using the given selectors to determine the inputs.
Returns a dictionary of results, keyed with the output names.
| Usage | Returns | ImageCollection.reduceColumns(reducer, selectors, weightSelectors) | Dictionary |
| Argument | Type | Details | this: collection | FeatureCollection | The collection to aggregate over. |
reducer | Reducer | The reducer to apply. |
selectors | List | A selector for each input of the reducer. |
weightSelectors | List, default: null | A selector for each weighted input of the reducer. |
Except as otherwise noted, the content of this page is licensed under the Creative Commons Attribution 4.0 License, and code samples are licensed under the Apache 2.0 License. For details, see the Google Developers Site Policies. Java is a registered trademark of Oracle and/or its affiliates.
Last updated 2023-10-06 UTC.
[null,null,["Last updated 2023-10-06 UTC."],[[["\u003cp\u003eThe \u003ccode\u003ereduceColumns\u003c/code\u003e method aggregates data from an ImageCollection using a specified reducer function and selected inputs.\u003c/p\u003e\n"],["\u003cp\u003eIt returns a dictionary containing the results, organized by output names specified in the reducer.\u003c/p\u003e\n"],["\u003cp\u003eUsers define input data through selectors and optionally assign weights to inputs using weightSelectors.\u003c/p\u003e\n"],["\u003cp\u003eThe function is available as a method on ImageCollections and accepts the reducer, selectors, and optional weightSelectors as arguments.\u003c/p\u003e\n"]]],["The function `reduceColumns` applies a reducer to each element in a FeatureCollection. It utilizes specified selectors to define reducer inputs and, optionally, weighted inputs. The function takes a reducer, a list of selectors, and an optional list of weight selectors as arguments. It returns a dictionary where keys are output names and values are the results of applying the reducer to the collection's elements.\n"],null,["# ee.ImageCollection.reduceColumns\n\nApply a reducer to each element of a collection, using the given selectors to determine the inputs.\n\n\u003cbr /\u003e\n\nReturns a dictionary of results, keyed with the output names.\n\n| Usage | Returns |\n|--------------------------------------------------------------------------|------------|\n| ImageCollection.reduceColumns`(reducer, selectors, `*weightSelectors*`)` | Dictionary |\n\n| Argument | Type | Details |\n|--------------------|---------------------|----------------------------------------------------|\n| this: `collection` | FeatureCollection | The collection to aggregate over. |\n| `reducer` | Reducer | The reducer to apply. |\n| `selectors` | List | A selector for each input of the reducer. |\n| `weightSelectors` | List, default: null | A selector for each weighted input of the reducer. |"]]