AI-generated Key Takeaways
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The convex hull of a geometry is returned.
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The convex hull of a single point is the point, of collinear points is a line, and of other geometries is a polygon.
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The
convexHullmethod accepts optionalmaxErrorandprojarguments for specifying reprojection error tolerance and the projection for the operation. -
The convex hull of a polygon can be calculated using the
convexHullmethod and displayed on a map, as shown in the JavaScript and Python examples.
| Usage | Returns |
|---|---|
Polygon.convexHull(maxError, proj) | Geometry |
| Argument | Type | Details |
|---|---|---|
this: geometry | Geometry | Calculates the convex hull of this geometry. |
maxError | ErrorMargin, default: null | The maximum amount of error tolerated when performing any necessary reprojection. |
proj | Projection, default: null | The 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 Polygon object. var polygon = ee.Geometry.Polygon( [[[-122.092, 37.424], [-122.086, 37.418], [-122.079, 37.425], [-122.085, 37.423]]]); // Apply the convexHull method to the Polygon object. var polygonConvexHull = polygon.convexHull({'maxError': 1}); // Print the result to the console. print('polygon.convexHull(...) =', polygonConvexHull); // Display relevant geometries on the map. Map.setCenter(-122.085, 37.422, 15); Map.addLayer(polygon, {'color': 'black'}, 'Geometry [black]: polygon'); Map.addLayer(polygonConvexHull, {'color': 'red'}, 'Result [red]: polygon.convexHull');
import ee import geemap.core as geemap
Colab (Python)
# Define a Polygon object. polygon = ee.Geometry.Polygon([[ [-122.092, 37.424], [-122.086, 37.418], [-122.079, 37.425], [-122.085, 37.423], ]]) # Apply the convexHull method to the Polygon object. polygon_convex_hull = polygon.convexHull(maxError=1) # Print the result. display('polygon.convexHull(...) =', polygon_convex_hull) # Display relevant geometries on the map. m = geemap.Map() m.set_center(-122.085, 37.422, 15) m.add_layer(polygon, {'color': 'black'}, 'Geometry [black]: polygon') m.add_layer( polygon_convex_hull, {'color': 'red'}, 'Result [red]: polygon.convexHull' ) m