ee.Geometry.centroid

Page Summary

• The Geometry.centroid() method returns a point at the center of the highest-dimension components of a geometry, ignoring lower-dimensional components.

• The method accepts optional maxError and proj arguments to control the accuracy of reprojection and the output projection.

• The centroid method can be applied to a Geometry object in both JavaScript and Python environments.

Returns a point at the center of the highest-dimension components of the geometry. Lower-dimensional components are ignored, so the centroid of a geometry containing two polygons, three lines and a point is equivalent to the centroid of a geometry containing just the two polygons.

Usage	Returns
Geometry.centroid(maxError, proj)	Geometry

Argument	Type	Details
this: geometry	Geometry	Calculates the centroid of this 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 this projection. Otherwise it will be in EPSG:4326.

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 centroid method to the Geometry object.
var geometryCentroid = geometry.centroid({'maxError': 1});

// Print the result to the console.
print('geometry.centroid(...) =', geometryCentroid);

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

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 centroid method to the Geometry object.
geometry_centroid = geometry.centroid(maxError=1)

# Print the result.
display('geometry.centroid(...) =', geometry_centroid)

# 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.add_layer(
    geometry_centroid, {'color': 'red'}, 'Result [red]: geometry.centroid'
)
m