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ee.ImageCollection.reduceColumns
透過集合功能整理內容
你可以依據偏好儲存及分類內容。
使用指定選取器判斷輸入內容，並將縮減器套用至集合中的每個元素。
傳回結果字典，並以輸出名稱做為鍵。
| 用量 | 傳回 |
|---|
ImageCollection.reduceColumns(reducer, selectors, weightSelectors) | 字典 |
| 引數 | 類型 | 詳細資料 |
|---|
這個：collection | FeatureCollection | 要匯總的集合。 |
reducer | 縮減函式 | 要套用的縮減函式。 |
selectors | 清單 | 每個縮減器輸入內容的選取器。 |
weightSelectors | 清單，預設值為空值 | 每個加權縮減輸入內容的選取器。 |
除非另有註明，否則本頁面中的內容是採用創用 CC 姓名標示 4.0 授權，程式碼範例則為阿帕契 2.0 授權。詳情請參閱《Google Developers 網站政策》。Java 是 Oracle 和/或其關聯企業的註冊商標。
上次更新時間：2025-07-26 (世界標準時間)。
[null,null,["上次更新時間：2025-07-26 (世界標準時間)。"],[[["\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. |"]]
