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ee.Reducer.median
透過集合功能整理內容
你可以依據偏好儲存及分類內容。
建立可計算輸入內容中位數的縮減器。如果輸入的數字不多 (最多 maxRaw 個)，系統會直接計算中位數；如果輸入的數字較多，系統會從直方圖推導出中位數。
| 用量 | 傳回 |
|---|
ee.Reducer.median(maxBuckets, minBucketWidth, maxRaw) | 縮減函式 |
| 引數 | 類型 | 詳細資料 |
|---|
maxBuckets | 整數，預設值為 null | 建構直方圖時使用的最大值範圍數量，會向上取整為 2 的乘方。 |
minBucketWidth | 浮點值，預設值為空值 | 直方圖儲存區寬度下限，或為空值，允許任何 2 的乘冪。 |
maxRaw | 整數，預設值為 null | 建構初始直方圖前要累積的值數量。 |
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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\u003eThis reducer calculates the median of input values, using either direct computation or a histogram-based approach depending on the input size.\u003c/p\u003e\n"],["\u003cp\u003eFor small datasets (up to \u003ccode\u003emaxRaw\u003c/code\u003e values), the median is computed directly from the raw input values.\u003c/p\u003e\n"],["\u003cp\u003eFor larger datasets, the reducer constructs a histogram with a maximum of \u003ccode\u003emaxBuckets\u003c/code\u003e, potentially rounding up to the nearest power of 2, and \u003ccode\u003eminBucketWidth\u003c/code\u003e as the minimum width of each bucket for efficient approximation.\u003c/p\u003e\n"],["\u003cp\u003eUsers can control the calculation process by specifying parameters like \u003ccode\u003emaxBuckets\u003c/code\u003e, \u003ccode\u003eminBucketWidth\u003c/code\u003e, and \u003ccode\u003emaxRaw\u003c/code\u003e to customize the reducer's behavior.\u003c/p\u003e\n"]]],["The core content describes a reducer that calculates the median of inputs. For smaller datasets (up to `maxRaw`), the median is directly computed. Larger datasets utilize a histogram for median derivation. The `ee.Reducer.median` function creates this reducer, accepting `maxBuckets` (maximum histogram buckets), `minBucketWidth` (minimum bucket size), and `maxRaw` (raw values threshold) as parameters to customize the histogram creation.\n"],null,["# ee.Reducer.median\n\nCreate a reducer that will compute the median of the inputs. For small numbers of inputs (up to maxRaw) the median will be computed directly; for larger numbers of inputs the median will be derived from a histogram.\n\n\u003cbr /\u003e\n\n| Usage | Returns |\n|-----------------------------------------------------------------------|---------|\n| `ee.Reducer.median(`*maxBuckets* `, `*minBucketWidth* `, `*maxRaw*`)` | Reducer |\n\n| Argument | Type | Details |\n|------------------|------------------------|-----------------------------------------------------------------------------------------------------|\n| `maxBuckets` | Integer, default: null | The maximum number of buckets to use when building a histogram; will be rounded up to a power of 2. |\n| `minBucketWidth` | Float, default: null | The minimum histogram bucket width, or null to allow any power of 2. |\n| `maxRaw` | Integer, default: null | The number of values to accumulate before building the initial histogram. |"]]
