Pointwise error estimates and local superconvergence of Jacobi expansions

Shuhuang Xiang, Desong Kong, Guidong Liu +1

As one myth of polynomial interpolation and quadrature, Trefethen [30] revealed that the Chebyshev interpolation of $|x-a|$ (with $|a|<1$) at the Clenshaw-Curtis points exhibited…