On rational interpolation to |x| at the quasi-equidistant nodes
ZHANG Huiming1， LI Jianjun2
(1.College of Mathematics and Physics， Hebei GEO University， Shijiazhuang 050031， China；2.Minzu College Affaliated to Hebei Normal University， Shijiazhuang 050091， China)
Abstract：In this paper， a new nodes is obtained by adding some nodes near the zero point based on the equidistant nodes foundation. The rational interpolation of |x|at this kind of nodes is studied， and it is obtained that the exact order of approximation is On2log n(1).This result is better than the rational interpolation of equidistant nodes， Chebyshev nodes (of the second kind)， adjusted Chebyshev nodes (of the second kind) and tangent nodes.
2022, Vol. 56 
