Error Formulas for Lagrange Projectors Determined by Cartesian Sets

摘要

This paper studies error formulas for Lagrange projectors determined by Cartesian sets.Cartesian sets are properly subgrids of tensor product grids.Given interpolated functions with all order continuous partial derivatives,the authors directly construct the good error formulas for Lagrange projectors determined by Cartesian sets.Owing to the special algebraic structure,such a good error formula is useful for error estimate.