ee.Geometry.LinearRing.convexHull

  • convexHull() returns the smallest convex Geometry that encloses the input geometry, which can be a point, line, or polygon.

  • The returned geometry can be a point, line segment, or polygon depending on the input geometry's structure and arrangement of vertices.

  • Optional parameters maxError and proj can be specified to control reprojection error and the projection used for the calculation.

  • For collinear points, the convex hull is a line segment representing the shortest line containing all points, while for a single point, it's the point itself.

 Returns the convex hull of the given geometry. The convex hull of a single point is the point itself, the convex hull of collinear points is a line, and the convex hull of everything else is a polygon. Note that a degenerate polygon with all vertices on the same line will result in a line segment.

UsageReturns
LinearRing.convexHull(maxError, proj)Geometry
ArgumentTypeDetails
this: geometryGeometryCalculates the convex hull of this geometry.
maxErrorErrorMargin, default: nullThe maximum amount of error tolerated when performing any necessary reprojection.
projProjection, default: nullThe projection in which to perform the operation. If not specified, the operation will be performed in a spherical coordinate system, and linear distances will be in meters on the sphere.

Examples

Code Editor (JavaScript)

// Define a LinearRing object.
var linearRing = ee.Geometry.LinearRing(
    [[-122.091, 37.420],
     [-122.085, 37.422],
     [-122.080, 37.430]]);

// Apply the convexHull method to the LinearRing object.
var linearRingConvexHull = linearRing.convexHull({'maxError': 1});

// Print the result to the console.
print('linearRing.convexHull(...) =', linearRingConvexHull);

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

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 LinearRing object.
linearring = ee.Geometry.LinearRing(
    [[-122.091, 37.420], [-122.085, 37.422], [-122.080, 37.430]]
)

# Apply the convexHull method to the LinearRing object.
linearring_convex_hull = linearring.convexHull(maxError=1)

# Print the result.
display('linearring.convexHull(...) =', linearring_convex_hull)

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