ee.Geometry.MultiPolygon.area

AI-generated Key Takeaways

• area() calculates and returns the area of a geometry object.

• Points and linestrings have an area of 0, while MultiPolygons sum the area of their parts.

• The area can be returned in square meters or in the units of a specified projection.

• This function can be applied to a MultiPolygon object using multiPolygon.area({'maxError': 1}) in JavaScript or multipolygon.area(maxError=1) in Python.

Returns the area of the geometry. Area of points and line strings is 0 and the area of multi geometries is the sum of the areas of their components (intersecting areas are counted multiple times).

Usage	Returns
MultiPolygon.area(maxError, proj)	Float

Argument	Type	Details
this: geometry	Geometry	The geometry input.
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 square meters.

Examples

Code Editor (JavaScript)

// Define a MultiPolygon object.
var multiPolygon = ee.Geometry.MultiPolygon(
    [[[[-122.092, 37.424],
       [-122.086, 37.418],
       [-122.079, 37.425],
       [-122.085, 37.423]]],
     [[[-122.081, 37.417],
       [-122.086, 37.421],
       [-122.089, 37.416]]]]);

// Apply the area method to the MultiPolygon object.
var multiPolygonArea = multiPolygon.area({'maxError': 1});

// Print the result to the console.
print('multiPolygon.area(...) =', multiPolygonArea);

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

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 MultiPolygon object.
multipolygon = ee.Geometry.MultiPolygon([
    [[
        [-122.092, 37.424],
        [-122.086, 37.418],
        [-122.079, 37.425],
        [-122.085, 37.423],
    ]],
    [[[-122.081, 37.417], [-122.086, 37.421], [-122.089, 37.416]]],
])

# Apply the area method to the MultiPolygon object.
multipolygon_area = multipolygon.area(maxError=1)

# Print the result.
display('multipolygon.area(...) =', multipolygon_area)

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