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arXiv · 1909.13399

A new bound for smooth spline spaces

Hal Schenck·Mike Stillman·Beihui Yuan
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Abstract

For a planar simplicial complex Delta contained in R^2, Schumaker proved that a lower bound on the dimension of the space C^r_k(Delta) of planar splines of smoothness r and polynomial degree at most k on Delta is given by a polynomial P_Delta(r,k), and Alfeld-Schumaker showed this polynomial gives the correct dimension when k >= 4r+1. Examples due to Morgan-Scott, Tohaneanu, and Yuan show that the equality dim C^r_k(Delta) = P_Delta(r,k) can fail when k = 2r or 2r+1. We prove that the equality dim C^r_k(Delta)= P_Delta(r,k) cannot hold in general for k <= (22r+7)/10.

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Hal Schenck, Mike Stillman, Beihui Yuan. 2020-05-08. A new bound for smooth spline spaces. https://arxiv.org/abs/1909.13399

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