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ee.Geometry.Polygon.length
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Returns the length of the linear parts of the geometry. Polygonal parts are ignored. The length of multi geometries is the sum of the lengths of their components.
| Usage | Returns | Polygon.length(maxError, proj) | Float |
| Argument | Type | Details | this: geometry | Geometry | The input geometry. |
maxError | ErrorMargin, default: null | The maximum amount of error tolerated when performing any necessary reprojection. |
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. |
Examples
Code Editor (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 length method to the Polygon object.
var polygonLength = polygon.length();
// Print the result to the console.
print('polygon.length(...) =', polygonLength);
// Display relevant geometries on the map.
Map.setCenter(-122.085, 37.422, 15);
Map.addLayer(polygon,
{'color': 'black'},
'Geometry [black]: polygon');
Python setup
See the
Python Environment page for information on the Python API and using
geemap for interactive development.
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 length method to the Polygon object.
polygon_length = polygon.length()
# Print the result.
display('polygon.length(...) =', polygon_length)
# 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
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Last updated 2023-10-06 UTC.
[null,null,["Last updated 2023-10-06 UTC."],[[["\u003cp\u003eCalculates the total length of a geometry's linear segments, excluding any polygonal areas.\u003c/p\u003e\n"],["\u003cp\u003eIt sums the lengths of individual components for multi-geometries.\u003c/p\u003e\n"],["\u003cp\u003eReturns the length in meters by default or in the units of a specified projection.\u003c/p\u003e\n"],["\u003cp\u003eCan be used with an optional \u003ccode\u003emaxError\u003c/code\u003e parameter to control reprojection accuracy.\u003c/p\u003e\n"]]],["The `length()` method calculates the length of linear parts within a geometry, ignoring polygonal sections. For multi-geometries, it sums the lengths of individual components. The method accepts optional `maxError` and `proj` arguments to define error tolerance and projection units, respectively. By default, length is computed in meters. The example demonstrates how to use `length()` on a polygon object and visualize it in JavaScript and Python environments.\n"],null,["# ee.Geometry.Polygon.length\n\nReturns the length of the linear parts of the geometry. Polygonal parts are ignored. The length of multi geometries is the sum of the lengths of their components.\n\n\u003cbr /\u003e\n\n| Usage | Returns |\n|-------------------------------------------|---------|\n| Polygon.length`(`*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 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 length method to the Polygon object.\nvar polygonLength = polygon.length();\n\n// Print the result to the console.\nprint('polygon.length(...) =', polygonLength);\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');\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 length method to the Polygon object.\npolygon_length = polygon.length()\n\n# Print the result.\ndisplay('polygon.length(...) =', polygon_length)\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\n```"]]