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ee.Geometry.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 |
---|
Geometry.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 Geometry object.
var geometry = ee.Geometry({
'type': 'Polygon',
'coordinates':
[[[-122.081, 37.417],
[-122.086, 37.421],
[-122.084, 37.418],
[-122.089, 37.416]]]
});
// Apply the centroid method to the Geometry object.
var geometryCentroid = geometry.centroid({'maxError': 1});
// Print the result to the console.
print('geometry.centroid(...) =', geometryCentroid);
// Display relevant geometries on the map.
Map.setCenter(-122.085, 37.422, 15);
Map.addLayer(geometry,
{'color': 'black'},
'Geometry [black]: geometry');
Map.addLayer(geometryCentroid,
{'color': 'red'},
'Result [red]: geometry.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 Geometry object.
geometry = ee.Geometry({
'type': 'Polygon',
'coordinates': [[
[-122.081, 37.417],
[-122.086, 37.421],
[-122.084, 37.418],
[-122.089, 37.416],
]],
})
# Apply the centroid method to the Geometry object.
geometry_centroid = geometry.centroid(maxError=1)
# Print the result.
display('geometry.centroid(...) =', geometry_centroid)
# Display relevant geometries on the map.
m = geemap.Map()
m.set_center(-122.085, 37.422, 15)
m.add_layer(geometry, {'color': 'black'}, 'Geometry [black]: geometry')
m.add_layer(
geometry_centroid, {'color': 'red'}, 'Result [red]: geometry.centroid'
)
m
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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\u003eReturns a central point based on the highest-dimension components of a geometry, ignoring lower dimensions.\u003c/p\u003e\n"],["\u003cp\u003e\u003ccode\u003ecentroid()\u003c/code\u003e can be applied to a Geometry object to compute its center point.\u003c/p\u003e\n"],["\u003cp\u003eOptional parameters \u003ccode\u003emaxError\u003c/code\u003e and \u003ccode\u003eproj\u003c/code\u003e control reprojection tolerance and output projection, respectively.\u003c/p\u003e\n"],["\u003cp\u003eThe default projection for the returned centroid is EPSG:4326 if \u003ccode\u003eproj\u003c/code\u003e is not specified.\u003c/p\u003e\n"]]],["The `Geometry.centroid()` method calculates the center point of the highest-dimensional components within a geometry, ignoring lower-dimensional parts. It accepts `maxError` for error tolerance during reprojection and `proj` to specify the output projection (defaulting to EPSG:4326). The method returns a `Geometry` object. Example usage in JavaScript and Python demonstrates defining a polygon geometry, finding its centroid, and displaying both on a map.\n"],null,["# ee.Geometry.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| Geometry.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 Geometry object.\nvar geometry = ee.Geometry({\n 'type': 'Polygon',\n 'coordinates':\n [[[-122.081, 37.417],\n [-122.086, 37.421],\n [-122.084, 37.418],\n [-122.089, 37.416]]]\n});\n\n// Apply the centroid method to the Geometry object.\nvar geometryCentroid = geometry.centroid({'maxError': 1});\n\n// Print the result to the console.\nprint('geometry.centroid(...) =', geometryCentroid);\n\n// Display relevant geometries on the map.\nMap.setCenter(-122.085, 37.422, 15);\nMap.addLayer(geometry,\n {'color': 'black'},\n 'Geometry [black]: geometry');\nMap.addLayer(geometryCentroid,\n {'color': 'red'},\n 'Result [red]: geometry.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 Geometry object.\ngeometry = ee.Geometry({\n 'type': 'Polygon',\n 'coordinates': [[\n [-122.081, 37.417],\n [-122.086, 37.421],\n [-122.084, 37.418],\n [-122.089, 37.416],\n ]],\n})\n\n# Apply the centroid method to the Geometry object.\ngeometry_centroid = geometry.centroid(maxError=1)\n\n# Print the result.\ndisplay('geometry.centroid(...) =', geometry_centroid)\n\n# Display relevant geometries on the map.\nm = geemap.Map()\nm.set_center(-122.085, 37.422, 15)\nm.add_layer(geometry, {'color': 'black'}, 'Geometry [black]: geometry')\nm.add_layer(\n geometry_centroid, {'color': 'red'}, 'Result [red]: geometry.centroid'\n)\nm\n```"]]