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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.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Missing the information I need","missingTheInformationINeed","thumb-down"],["Too complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2023-10-06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```"]]