{ "id": "1310.2283", "version": "v2", "published": "2013-10-08T21:32:18.000Z", "updated": "2013-11-08T19:15:31.000Z", "title": "Spectral approximation on the unit ball", "authors": [ "Huiyuan Li", "Yuan Xu" ], "comment": "28 pages, 3 figures", "categories": [ "math.CA", "math.NA" ], "abstract": "Spectral approximation by polynomials on the unit ball is studied in the frame of the Sobolev spaces $W^{s}_p(\\ball)$, $1