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ee.Geometry.MultiLineString.difference
透過集合功能整理內容
你可以依據偏好儲存及分類內容。
傳回從「左」幾何圖形減去「右」幾何圖形的結果。
用量 | 傳回 |
---|
MultiLineString.difference(right, maxError, proj) | 幾何圖形 |
引數 | 類型 | 詳細資料 |
---|
這個:left | 幾何圖形 | 做為運算左運算元的幾何圖形。 |
right | 幾何圖形 | 用做運算右運算元的幾何圖形。 |
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 | 執行作業的投影。如未指定,系統會以球面座標系統執行作業,而球面上的線性距離會以公尺為單位。 |
範例
程式碼編輯器 (JavaScript)
// Define a MultiLineString object.
var multiLineString = ee.Geometry.MultiLineString(
[[[-122.088, 37.418], [-122.086, 37.422], [-122.082, 37.418]],
[[-122.087, 37.416], [-122.083, 37.416], [-122.082, 37.419]]]);
// Define other inputs.
var inputGeom = ee.Geometry.BBox(-122.085, 37.415, -122.075, 37.425);
// Apply the difference method to the MultiLineString object.
var multiLineStringDifference = multiLineString.difference({'right': inputGeom, 'maxError': 1});
// Print the result to the console.
print('multiLineString.difference(...) =', multiLineStringDifference);
// Display relevant geometries on the map.
Map.setCenter(-122.085, 37.422, 15);
Map.addLayer(multiLineString,
{'color': 'black'},
'Geometry [black]: multiLineString');
Map.addLayer(inputGeom,
{'color': 'blue'},
'Parameter [blue]: inputGeom');
Map.addLayer(multiLineStringDifference,
{'color': 'red'},
'Result [red]: multiLineString.difference');
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 MultiLineString object.
multilinestring = ee.Geometry.MultiLineString([
[[-122.088, 37.418], [-122.086, 37.422], [-122.082, 37.418]],
[[-122.087, 37.416], [-122.083, 37.416], [-122.082, 37.419]],
])
# Define other inputs.
input_geom = ee.Geometry.BBox(-122.085, 37.415, -122.075, 37.425)
# Apply the difference method to the MultiLineString object.
multilinestring_difference = multilinestring.difference(
right=input_geom, maxError=1
)
# Print the result.
display('multilinestring.difference(...) =', multilinestring_difference)
# Display relevant geometries on the map.
m = geemap.Map()
m.set_center(-122.085, 37.422, 15)
m.add_layer(
multilinestring, {'color': 'black'}, 'Geometry [black]: multilinestring'
)
m.add_layer(input_geom, {'color': 'blue'}, 'Parameter [blue]: input_geom')
m.add_layer(
multilinestring_difference,
{'color': 'red'},
'Result [red]: multilinestring.difference',
)
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\u003eThe \u003ccode\u003edifference()\u003c/code\u003e method returns a Geometry representing the portions of the 'left' geometry that do not intersect with the 'right' geometry.\u003c/p\u003e\n"],["\u003cp\u003eIt is used on MultiLineString geometries in Earth Engine to remove areas covered by a second geometry.\u003c/p\u003e\n"],["\u003cp\u003eThe operation can be performed using a specified projection or, by default, in a spherical coordinate system with distances in meters.\u003c/p\u003e\n"],["\u003cp\u003eOptional parameters \u003ccode\u003emaxError\u003c/code\u003e and \u003ccode\u003eproj\u003c/code\u003e control the reprojection tolerance and projection used during the operation, respectively.\u003c/p\u003e\n"]]],[],null,["# ee.Geometry.MultiLineString.difference\n\nReturns the result of subtracting the 'right' geometry from the 'left' geometry.\n\n\u003cbr /\u003e\n\n| Usage | Returns |\n|--------------------------------------------------------------|----------|\n| MultiLineString.difference`(right, `*maxError* `, `*proj*`)` | Geometry |\n\n| Argument | Type | Details |\n|--------------|----------------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|\n| this: `left` | Geometry | The geometry used as the left operand of the operation. |\n| `right` | Geometry | The geometry used as the right operand of the operation. |\n| `maxError` | ErrorMargin, default: null | The maximum amount of error tolerated when performing any necessary reprojection. |\n| `proj` | Projection, default: null | The projection in which to perform the operation. If not specified, the operation will be performed in a spherical coordinate system, and linear distances will be in meters on the sphere. |\n\nExamples\n--------\n\n### Code Editor (JavaScript)\n\n```javascript\n// Define a MultiLineString object.\nvar multiLineString = ee.Geometry.MultiLineString(\n [[[-122.088, 37.418], [-122.086, 37.422], [-122.082, 37.418]],\n [[-122.087, 37.416], [-122.083, 37.416], [-122.082, 37.419]]]);\n\n// Define other inputs.\nvar inputGeom = ee.Geometry.BBox(-122.085, 37.415, -122.075, 37.425);\n\n// Apply the difference method to the MultiLineString object.\nvar multiLineStringDifference = multiLineString.difference({'right': inputGeom, 'maxError': 1});\n\n// Print the result to the console.\nprint('multiLineString.difference(...) =', multiLineStringDifference);\n\n// Display relevant geometries on the map.\nMap.setCenter(-122.085, 37.422, 15);\nMap.addLayer(multiLineString,\n {'color': 'black'},\n 'Geometry [black]: multiLineString');\nMap.addLayer(inputGeom,\n {'color': 'blue'},\n 'Parameter [blue]: inputGeom');\nMap.addLayer(multiLineStringDifference,\n {'color': 'red'},\n 'Result [red]: multiLineString.difference');\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 MultiLineString object.\nmultilinestring = ee.Geometry.MultiLineString([\n [[-122.088, 37.418], [-122.086, 37.422], [-122.082, 37.418]],\n [[-122.087, 37.416], [-122.083, 37.416], [-122.082, 37.419]],\n])\n\n# Define other inputs.\ninput_geom = ee.Geometry.BBox(-122.085, 37.415, -122.075, 37.425)\n\n# Apply the difference method to the MultiLineString object.\nmultilinestring_difference = multilinestring.difference(\n right=input_geom, maxError=1\n)\n\n# Print the result.\ndisplay('multilinestring.difference(...) =', multilinestring_difference)\n\n# Display relevant geometries on the map.\nm = geemap.Map()\nm.set_center(-122.085, 37.422, 15)\nm.add_layer(\n multilinestring, {'color': 'black'}, 'Geometry [black]: multilinestring'\n)\nm.add_layer(input_geom, {'color': 'blue'}, 'Parameter [blue]: input_geom')\nm.add_layer(\n multilinestring_difference,\n {'color': 'red'},\n 'Result [red]: multilinestring.difference',\n)\nm\n```"]]