Abstract:
We obtain an estimate of the norm of the Lagrange interpolation operator in a multidimensional Sobolev space. It is shown that, under a suitable choice of the sequence of multi-indices, interpolation polynomials converge to the interpolated function and their rate of convergence is of the order of the best approximation of this function.
Keywords:Lagrange interpolation operator, interpolation polynomial, rate of convergence, best approximation, Sobolev space, Hilbert space.