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ee.Geometry.Polygon.buffer
透過集合功能整理內容
你可以依據偏好儲存及分類內容。
傳回緩衝指定距離的輸入內容。如果距離為正值,幾何圖形會擴大;如果距離為負值,幾何圖形會縮小。
用量 | 傳回 |
---|
Polygon.buffer(distance, maxError, proj) | 幾何圖形 |
引數 | 類型 | 詳細資料 |
---|
這個:geometry | 幾何圖形 | 正在緩衝處理的幾何圖形。 |
distance | 浮點值 | 緩衝區的距離,可能為負值。如未指定投影,則單位為公尺。否則單位會採用投影的座標系統。 |
maxError | ErrorMargin,預設值:null | 近似緩衝圓圈和執行任何必要重新投影時,可容許的最大誤差量。如未指定,則預設為距離的 1%。 |
proj | 投影,預設值:null | 如果指定,緩衝區會在這個投影中執行,距離會解讀為這個投影的座標系統單位。否則,系統會將距離解讀為公尺,並在球體座標系統中執行緩衝處理。 |
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 buffer method to the Polygon object.
var polygonBuffer = polygon.buffer({'distance': 100});
// Print the result to the console.
print('polygon.buffer(...) =', polygonBuffer);
// Display relevant geometries on the map.
Map.setCenter(-122.085, 37.422, 15);
Map.addLayer(polygon,
{'color': 'black'},
'Geometry [black]: polygon');
Map.addLayer(polygonBuffer,
{'color': 'red'},
'Result [red]: polygon.buffer');
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 buffer method to the Polygon object.
polygon_buffer = polygon.buffer(distance=100)
# Print the result.
display('polygon.buffer(...) =', polygon_buffer)
# 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_buffer, {'color': 'red'}, 'Result [red]: polygon.buffer')
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\u003e\u003ccode\u003ebuffer()\u003c/code\u003e returns a Geometry that is the input geometry expanded or contracted by a given distance.\u003c/p\u003e\n"],["\u003cp\u003ePositive distance values expand the geometry while negative values contract it.\u003c/p\u003e\n"],["\u003cp\u003eThe distance is in meters unless a projection (\u003ccode\u003eproj\u003c/code\u003e) is specified, in which case the distance is in the units of that projection's coordinate system.\u003c/p\u003e\n"],["\u003cp\u003eAn optional \u003ccode\u003emaxError\u003c/code\u003e parameter controls the accuracy of the buffer approximation.\u003c/p\u003e\n"]]],[],null,["# ee.Geometry.Polygon.buffer\n\nReturns the input buffered by a given distance. If the distance is positive, the geometry is expanded, and if the distance is negative, the geometry is contracted.\n\n\u003cbr /\u003e\n\n| Usage | Returns |\n|-----------------------------------------------------|----------|\n| Polygon.buffer`(distance, `*maxError* `, `*proj*`)` | Geometry |\n\n| Argument | Type | Details |\n|------------------|----------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|\n| this: `geometry` | Geometry | The geometry being buffered. |\n| `distance` | Float | The distance of the buffering, which may be negative. If no projection is specified, the unit is meters. Otherwise the unit is in the coordinate system of the projection. |\n| `maxError` | ErrorMargin, default: null | The maximum amount of error tolerated when approximating the buffering circle and performing any necessary reprojection. If unspecified, defaults to 1% of the distance. |\n| `proj` | Projection, default: null | If specified, the buffering will be performed in this projection and the distance will be interpreted as units of the coordinate system of this projection. Otherwise the distance is interpereted as meters and the buffering is performed in a spherical coordinate system. |\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 buffer method to the Polygon object.\nvar polygonBuffer = polygon.buffer({'distance': 100});\n\n// Print the result to the console.\nprint('polygon.buffer(...) =', polygonBuffer);\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(polygonBuffer,\n {'color': 'red'},\n 'Result [red]: polygon.buffer');\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 buffer method to the Polygon object.\npolygon_buffer = polygon.buffer(distance=100)\n\n# Print the result.\ndisplay('polygon.buffer(...) =', polygon_buffer)\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(polygon_buffer, {'color': 'red'}, 'Result [red]: polygon.buffer')\nm\n```"]]