Localized Bases for Kernel Spaces on the Unit Sphere
Localized Bases for Kernel Spaces on the Unit Sphere
复制标题
单位球面上核空间的局部化基
DOI:
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复制
发表时间:
2012
影响因子:
2.9
通讯作者:
G. Wright
中科院分区:
文献类型:
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作者:
E. Fuselier;T. Hangelbroek;F. Narcowich;J. Ward;G. Wright
Approximation/interpolation from spaces of positive definite or conditionally positive definite kernels is an increasingly popular tool for the analysis and synthesis of scattered data and is central to many meshless methods. For a set of $N$ scattered sites, the standard basis for such a space utilizes $N$ globally supported kernels; computing with it is prohibitively expensive for large $N$. Easily computable, well-localized bases with “small-footprint” basis elements---i.e., elements using only a small number of kernels---have been unavailable. Working on $\mathbb{S}^2$, with focus on the restricted surface spline kernels (e.g., the thin-plate splines restricted to the sphere), we construct easily computable, spatially well-localized, small-footprint, robust bases for the associated kernel spaces. Our theory predicts that each element of the local basis is constructed by using a combination of only $\mathcal{O}((\log N)^2)$ kernels, which makes the construction computationally cheap. We prove that the ...