ee.Geometry.perimeter

  • Returns the length of the perimeter of a geometry, including the sum of perimeters for multi-geometries.

  • Accepts optional maxError and proj arguments for reprojection and unit specification.

  • Results are in meters unless a projection is specified with the proj argument.

  • Can be applied to ee.Geometry objects in both JavaScript and Python environments within Google Earth Engine.

 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.

UsageReturns
Geometry.perimeter(maxError, proj)Float
ArgumentTypeDetails
this: geometryGeometryThe input geometry.
maxErrorErrorMargin, default: nullThe maximum amount of error tolerated when performing any necessary reprojection.
projProjection, default: nullIf 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 Geometry object.
var geometry = ee.Geometry({
  'type': 'Polygon',
  'coordinates':
    [[[-122.081, 37.417],
      [-122.086, 37.421],
      [-122.084, 37.418],
      [-122.089, 37.416]]]
});

// Apply the perimeter method to the Geometry object.
var geometryPerimeter = geometry.perimeter({'maxError': 1});

// Print the result to the console.
print('geometry.perimeter(...) =', geometryPerimeter);

// Display relevant geometries on the map.
Map.setCenter(-122.085, 37.422, 15);
Map.addLayer(geometry,
             {'color': 'black'},
             'Geometry [black]: geometry');

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 Geometry object.
geometry = ee.Geometry({
    'type': 'Polygon',
    'coordinates': [[
        [-122.081, 37.417],
        [-122.086, 37.421],
        [-122.084, 37.418],
        [-122.089, 37.416],
    ]],
})

# Apply the perimeter method to the Geometry object.
geometry_perimeter = geometry.perimeter(maxError=1)

# Print the result.
display('geometry.perimeter(...) =', geometry_perimeter)

# Display relevant geometries on the map.
m = geemap.Map()
m.set_center(-122.085, 37.422, 15)
m.add_layer(geometry, {'color': 'black'}, 'Geometry [black]: geometry')
m