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Returns 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.
Usage
Returns
Polygon.perimeter(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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2023-10-06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 all the sides of a polygon or the sum of perimeters for multi-part polygons.\u003c/p\u003e\n"],["\u003cp\u003eReturns the perimeter value as a float, which can be in meters or the units of a specified projection.\u003c/p\u003e\n"],["\u003cp\u003eAccepts optional parameters for error tolerance during reprojection (\u003ccode\u003emaxError\u003c/code\u003e) and output projection (\u003ccode\u003eproj\u003c/code\u003e).\u003c/p\u003e\n"],["\u003cp\u003eCan be applied to Geometry objects using the \u003ccode\u003eperimeter()\u003c/code\u003e method in both JavaScript and Python.\u003c/p\u003e\n"]]],["The `perimeter()` method calculates the total perimeter length of a geometry's polygonal parts. For multi-geometries, it sums the perimeters of each component. It accepts `maxError` to control reprojection accuracy and `proj` to set the output units (defaulting to meters). The method returns a float value. The example demonstrates its use on a polygon, calculating and then displaying its perimeter, and displaying the polygon on a map.\n"],null,["# ee.Geometry.Polygon.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| Polygon.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 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 perimeter method to the Polygon object.\nvar polygonPerimeter = polygon.perimeter({'maxError': 1});\n\n// Print the result to the console.\nprint('polygon.perimeter(...) =', polygonPerimeter);\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 perimeter method to the Polygon object.\npolygon_perimeter = polygon.perimeter(maxError=1)\n\n# Print the result.\ndisplay('polygon.perimeter(...) =', polygon_perimeter)\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```"]]