X-Nico

unusual facts about convex hull



Binary tetrahedral group

The convex hull of these 24 elements in 4-dimensional space form a convex regular 4-polytope called the 24-cell.

Context of computational complexity

For example, Chan's algorithm can compute the convex hull of a set of points in O(n log h) time, where n is the number of points in the input and h is the number of points in the resulting convex hull, a subset of the input points.

Oloid

It is the convex hull of a skeletal frame made by placing two linked congruent circles in perpendicular planes, so that the center of each circle lies on the other circle.

Pitteway triangulation

When such a triangulation exists it is a special case of the Delaunay triangulation, and consists of the union of the Gabriel graph and convex hull.

Thus, a circle having that edge as diameter must be empty of vertices, so the Pitteway triangulation consists of the Gabriel graph together with the convex hull of the point set.


see also