We consider piecewise linear interpolation from the perspective of kernel interpolation and quadrature. If the Sobolev space W12(0,1) is equipped with a suitable inner product, its reproducing kernel is piecewise linear and gives rise to piecewise linear interpolation. We show that such kernels are Green kernels for certain second-order partial differential equations and use kernel-based superconvergence theory to obtain rates of convergence for approximation of functions lying in Ws2(0,1) for s∈[1,2]. The rates coincide with classical rates for linear splines.
misc KSW+26
BibTeXKey: KSW+26