Cheng, Hao; Fang, Shu-Cherng; Lavery, John E. - In: Computational Statistics 56 (2002) 2, pp. 197-229
Univariate cubic L 1 splines provide C 1 -smooth, shape-preserving interpolation of arbitrary data, including data with abrupt changes in spacing and magnitude. The minimization principle for univariate cubic L 1 splines results in a nondifferentiable convex optimization problem. In order to...