ee.Geometry.LineString.convexHull

  • Returns the smallest convex Geometry that contains all the points in the input Geometry.

  • The returned Geometry type can be a Point, LineString, or Polygon depending on the input Geometry.

  • Accepts optional maxError and proj parameters for reprojection control.

  • The convex hull of a single point is the point itself; the convex hull of collinear points is a line; the convex hull of everything else is a polygon.

 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
LineString.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 LineString object.
var lineString = ee.Geometry.LineString([[-122.09, 37.42], [-122.08, 37.43]]);

// Apply the convexHull method to the LineString object.
var lineStringConvexHull = lineString.convexHull({'maxError': 1});

// Print the result to the console.
print('lineString.convexHull(...) =', lineStringConvexHull);

// Display relevant geometries on the map.
Map.setCenter(-122.085, 37.422, 15);
Map.addLayer(lineString,
             {'color': 'black'},
             'Geometry [black]: lineString');
Map.addLayer(lineStringConvexHull,
             {'color': 'red'},
             'Result [red]: lineString.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 LineString object.
linestring = ee.Geometry.LineString([[-122.09, 37.42], [-122.08, 37.43]])

# Apply the convexHull method to the LineString object.
linestring_convex_hull = linestring.convexHull(maxError=1)

# Print the result.
display('linestring.convexHull(...) =', linestring_convex_hull)

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