公告:凡是在
2025 年 4 月 15 日前註冊使用 Earth Engine 的非商業專案,都必須
驗證非商業用途資格,才能繼續存取 Earth Engine。
ee.Geometry.Polygon.centroid
透過集合功能整理內容
你可以依據偏好儲存及分類內容。
傳回幾何體最高維度元件中心的點。系統會忽略低維度元件,因此含有兩個多邊形、三條線和一個點的幾何圖形質心,等同於只含有兩個多邊形的幾何圖形質心。
用量 | 傳回 |
---|
Polygon.centroid(maxError, proj) | 幾何圖形 |
引數 | 類型 | 詳細資料 |
---|
這個:geometry | 幾何圖形 | 計算這個幾何體的重心。 |
maxError | ErrorMargin,預設值:null | 執行任何必要重投影時可容許的最大誤差量。 |
proj | 投影,預設值:null | 如果指定,結果會以這個投影方式呈現。否則會採用 EPSG:4326。 |
範例
程式碼編輯器 (JavaScript)
// Define a Polygon object.
var polygon = ee.Geometry.Polygon(
[[[-122.092, 37.424],
[-122.086, 37.418],
[-122.079, 37.425],
[-122.085, 37.423]]]);
// Apply the centroid method to the Polygon object.
var polygonCentroid = polygon.centroid({'maxError': 1});
// Print the result to the console.
print('polygon.centroid(...) =', polygonCentroid);
// Display relevant geometries on the map.
Map.setCenter(-122.085, 37.422, 15);
Map.addLayer(polygon,
{'color': 'black'},
'Geometry [black]: polygon');
Map.addLayer(polygonCentroid,
{'color': 'red'},
'Result [red]: polygon.centroid');
Python 設定
請參閱
Python 環境頁面,瞭解 Python API 和如何使用 geemap
進行互動式開發。
import ee
import geemap.core as geemap
Colab (Python)
# Define a Polygon object.
polygon = ee.Geometry.Polygon([[
[-122.092, 37.424],
[-122.086, 37.418],
[-122.079, 37.425],
[-122.085, 37.423],
]])
# Apply the centroid method to the Polygon object.
polygon_centroid = polygon.centroid(maxError=1)
# Print the result.
display('polygon.centroid(...) =', polygon_centroid)
# Display relevant geometries on the map.
m = geemap.Map()
m.set_center(-122.085, 37.422, 15)
m.add_layer(polygon, {'color': 'black'}, 'Geometry [black]: polygon')
m.add_layer(
polygon_centroid, {'color': 'red'}, 'Result [red]: polygon.centroid'
)
m
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\u003e\u003ccode\u003ecentroid()\u003c/code\u003e returns the center point of the highest-dimension components of a geometry, ignoring lower dimensions.\u003c/p\u003e\n"],["\u003cp\u003eIt is applicable to \u003ccode\u003ePolygon\u003c/code\u003e geometries and can be customized with \u003ccode\u003emaxError\u003c/code\u003e for reprojection tolerance and \u003ccode\u003eproj\u003c/code\u003e for output projection.\u003c/p\u003e\n"],["\u003cp\u003eThe result is a new \u003ccode\u003eGeometry\u003c/code\u003e object representing the calculated centroid.\u003c/p\u003e\n"],["\u003cp\u003eIf \u003ccode\u003eproj\u003c/code\u003e is not specified, the centroid coordinates will be in EPSG:4326.\u003c/p\u003e\n"]]],[],null,["# ee.Geometry.Polygon.centroid\n\nReturns a point at the center of the highest-dimension components of the geometry. Lower-dimensional components are ignored, so the centroid of a geometry containing two polygons, three lines and a point is equivalent to the centroid of a geometry containing just the two polygons.\n\n\u003cbr /\u003e\n\n| Usage | Returns |\n|---------------------------------------------|----------|\n| Polygon.centroid`(`*maxError* `, `*proj*`)` | Geometry |\n\n| Argument | Type | Details |\n|------------------|----------------------------|-----------------------------------------------------------------------------------------|\n| this: `geometry` | Geometry | Calculates the centroid of this geometry. |\n| `maxError` | ErrorMargin, default: null | The maximum amount of error tolerated when performing any necessary reprojection. |\n| `proj` | Projection, default: null | If specified, the result will be in this projection. Otherwise it will be in EPSG:4326. |\n\nExamples\n--------\n\n### Code Editor (JavaScript)\n\n```javascript\n// Define a Polygon object.\nvar polygon = ee.Geometry.Polygon(\n [[[-122.092, 37.424],\n [-122.086, 37.418],\n [-122.079, 37.425],\n [-122.085, 37.423]]]);\n\n// Apply the centroid method to the Polygon object.\nvar polygonCentroid = polygon.centroid({'maxError': 1});\n\n// Print the result to the console.\nprint('polygon.centroid(...) =', polygonCentroid);\n\n// Display relevant geometries on the map.\nMap.setCenter(-122.085, 37.422, 15);\nMap.addLayer(polygon,\n {'color': 'black'},\n 'Geometry [black]: polygon');\nMap.addLayer(polygonCentroid,\n {'color': 'red'},\n 'Result [red]: polygon.centroid');\n```\nPython setup\n\nSee the [Python Environment](/earth-engine/guides/python_install) page for information on the Python API and using\n`geemap` for interactive development. \n\n```python\nimport ee\nimport geemap.core as geemap\n```\n\n### Colab (Python)\n\n```python\n# Define a Polygon object.\npolygon = ee.Geometry.Polygon([[\n [-122.092, 37.424],\n [-122.086, 37.418],\n [-122.079, 37.425],\n [-122.085, 37.423],\n]])\n\n# Apply the centroid method to the Polygon object.\npolygon_centroid = polygon.centroid(maxError=1)\n\n# Print the result.\ndisplay('polygon.centroid(...) =', polygon_centroid)\n\n# Display relevant geometries on the map.\nm = geemap.Map()\nm.set_center(-122.085, 37.422, 15)\nm.add_layer(polygon, {'color': 'black'}, 'Geometry [black]: polygon')\nm.add_layer(\n polygon_centroid, {'color': 'red'}, 'Result [red]: polygon.centroid'\n)\nm\n```"]]