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arXiv · 0811.4175

Polyharmonic approximation on the sphere

Thomas Hangelbroek
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Abstract

The purpose of this article is to provide new error estimates for a popular type of SBF approximation on the sphere: approximating by linear combinations of Green's functions of polyharmonic differential operators. We show that the $L_p$ approximation order for this kind of approximation is $\sigma$ for functions having $L_p$ smoothness $\sigma$ (for $\sigma$ up to the order of the underlying differential operator, just as in univariate spline theory). This is an improvement over previous error estimates, which penalized the approximation order when measuring error in $L_p$, p>2 and held only in a restrictive setting when measuring error in $L_p$, p<2.

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Thomas Hangelbroek. 2008-11-25. Polyharmonic approximation on the sphere. https://doi.org/10.1007/s00365-010-9093-8

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