A Sixth-Order Accurate Direct Solver for the Poisson and Helmholtz Equations.

摘要

An O(h6) accurate direct solver is described for a class of separable elliptic equations in (r,0) coordinates with periodic conditions in 0. A discrete Fourier transform is used in 0, and the Hermite 6 discretization of Rubin and Khosla is used in r. A single deferred correction at boundary points gives the O(h6) accuracy, in O(N21nN) operations for an NxN problem. (Author)