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ee.Geometry.MultiPolygon.perimeter
使用集合让一切井井有条
根据您的偏好保存内容并对其进行分类。
返回几何图形的多边形部分的周长。多几何图形的周长是其组成部分的周长之和。
用法 | 返回 |
---|
MultiPolygon.perimeter(maxError, proj) | 浮点数 |
参数 | 类型 | 详细信息 |
---|
此:geometry | 几何图形 | 输入几何图形。 |
maxError | ErrorMargin,默认值:null | 执行任何必要的重新投影时可容忍的最大误差量。 |
proj | 投影,默认值:null | 如果指定,结果将采用相应投影的坐标系的单位。否则将以米为单位。 |
示例
代码编辑器 (JavaScript)
// Define a MultiPolygon object.
var multiPolygon = ee.Geometry.MultiPolygon(
[[[[-122.092, 37.424],
[-122.086, 37.418],
[-122.079, 37.425],
[-122.085, 37.423]]],
[[[-122.081, 37.417],
[-122.086, 37.421],
[-122.089, 37.416]]]]);
// Apply the perimeter method to the MultiPolygon object.
var multiPolygonPerimeter = multiPolygon.perimeter({'maxError': 1});
// Print the result to the console.
print('multiPolygon.perimeter(...) =', multiPolygonPerimeter);
// Display relevant geometries on the map.
Map.setCenter(-122.085, 37.422, 15);
Map.addLayer(multiPolygon,
{'color': 'black'},
'Geometry [black]: multiPolygon');
Python 设置
如需了解 Python API 和如何使用 geemap
进行交互式开发,请参阅
Python 环境页面。
import ee
import geemap.core as geemap
Colab (Python)
# Define a MultiPolygon object.
multipolygon = ee.Geometry.MultiPolygon([
[[
[-122.092, 37.424],
[-122.086, 37.418],
[-122.079, 37.425],
[-122.085, 37.423],
]],
[[[-122.081, 37.417], [-122.086, 37.421], [-122.089, 37.416]]],
])
# Apply the perimeter method to the MultiPolygon object.
multipolygon_perimeter = multipolygon.perimeter(maxError=1)
# Print the result.
display('multipolygon.perimeter(...) =', multipolygon_perimeter)
# Display relevant geometries on the map.
m = geemap.Map()
m.set_center(-122.085, 37.422, 15)
m.add_layer(
multipolygon, {'color': 'black'}, 'Geometry [black]: multipolygon'
)
m
如未另行说明,那么本页面中的内容已根据知识共享署名 4.0 许可获得了许可,并且代码示例已根据 Apache 2.0 许可获得了许可。有关详情,请参阅 Google 开发者网站政策。Java 是 Oracle 和/或其关联公司的注册商标。
最后更新时间 (UTC):2025-07-26。
[null,null,["最后更新时间 (UTC):2025-07-26。"],[[["\u003cp\u003eCalculates the total length of all the outer edges of a MultiPolygon geometry.\u003c/p\u003e\n"],["\u003cp\u003eThe perimeter of a MultiPolygon is the sum of the perimeters of all its individual polygons.\u003c/p\u003e\n"],["\u003cp\u003eAccepts optional parameters for projection and error tolerance during calculations.\u003c/p\u003e\n"],["\u003cp\u003eReturns the perimeter value as a float, representing the total distance in meters or the specified projection's units.\u003c/p\u003e\n"]]],["The `perimeter()` method calculates the total perimeter of a geometry's polygonal parts. For MultiPolygon geometries, it sums the perimeters of each component. It accepts optional `maxError` and `proj` arguments to control reprojection accuracy and output units. The method returns a float representing the perimeter length. Examples demonstrate its usage in both JavaScript and Python, calculating and displaying the perimeter of a MultiPolygon. The units will be in meters unless a different projection is defined.\n"],null,["# ee.Geometry.MultiPolygon.perimeter\n\nReturns the length of the perimeter of the polygonal parts of the geometry. The perimeter of multi geometries is the sum of the perimeters of their components.\n\n\u003cbr /\u003e\n\n| Usage | Returns |\n|---------------------------------------------------|---------|\n| MultiPolygon.perimeter`(`*maxError* `, `*proj*`)` | Float |\n\n| Argument | Type | Details |\n|------------------|----------------------------|----------------------------------------------------------------------------------------------------------------------------|\n| this: `geometry` | Geometry | The input 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 the units of the coordinate system of this projection. Otherwise it will be in meters. |\n\nExamples\n--------\n\n### Code Editor (JavaScript)\n\n```javascript\n// Define a MultiPolygon object.\nvar multiPolygon = ee.Geometry.MultiPolygon(\n [[[[-122.092, 37.424],\n [-122.086, 37.418],\n [-122.079, 37.425],\n [-122.085, 37.423]]],\n [[[-122.081, 37.417],\n [-122.086, 37.421],\n [-122.089, 37.416]]]]);\n\n// Apply the perimeter method to the MultiPolygon object.\nvar multiPolygonPerimeter = multiPolygon.perimeter({'maxError': 1});\n\n// Print the result to the console.\nprint('multiPolygon.perimeter(...) =', multiPolygonPerimeter);\n\n// Display relevant geometries on the map.\nMap.setCenter(-122.085, 37.422, 15);\nMap.addLayer(multiPolygon,\n {'color': 'black'},\n 'Geometry [black]: multiPolygon');\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 MultiPolygon object.\nmultipolygon = ee.Geometry.MultiPolygon([\n [[\n [-122.092, 37.424],\n [-122.086, 37.418],\n [-122.079, 37.425],\n [-122.085, 37.423],\n ]],\n [[[-122.081, 37.417], [-122.086, 37.421], [-122.089, 37.416]]],\n])\n\n# Apply the perimeter method to the MultiPolygon object.\nmultipolygon_perimeter = multipolygon.perimeter(maxError=1)\n\n# Print the result.\ndisplay('multipolygon.perimeter(...) =', multipolygon_perimeter)\n\n# Display relevant geometries on the map.\nm = geemap.Map()\nm.set_center(-122.085, 37.422, 15)\nm.add_layer(\n multipolygon, {'color': 'black'}, 'Geometry [black]: multipolygon'\n)\nm\n```"]]