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R Implementation of a Polyhedral Approximation to a 3D Set of Points Using the Alpha-Shape
Published
Author(s)
Thomas V. Lafarge, Beatriz Pateiro Lopez, Antonio M. Possolo, Joy P. Dunkers
Abstract
This work describes the implementation in R of the alpha-shape of a finite set of points in three-dimensional space. This geometric construct generalizes the convex hull and estimates the shape of non-convex and even non-connected sets in 3D, given random samples of points drawn from them. Besides the computation of the alpha-shape, the R package alphashape3d provides users with tools to facilitate the three-dimensional graphical visualization of the estimated set, as well as the computation of geometrical attributes that include the connected components, surface area, volume, porosity, and connectivity, among others.
Lafarge, T.
, Pateiro, B.
, Possolo, A.
and Dunkers, J.
(2014),
R Implementation of a Polyhedral Approximation to a 3D Set of Points Using the Alpha-Shape, Journal of Statistical Software, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=911704
(Accessed October 18, 2025)