REMARKS ON THE SOLUTION OF POISSONS EQUATION FOR ISOLATED SYSTEMS

A discussion of the solution by means of fast fourier transforms of the constant coefficient elliptic problem with isolated boundary conditions is presented. Concepts of filtering and sampling are used to show that the transform algorithm devised by Hockney [1] gives exact potential values in the computational box (c.f. remarks in [2]). The algorithm and performance of a three dimensional implementation of the transform algorithm is given. It is shown that interlaced meshes or mesh and submeshes may be employed to gain further computational economy. © 1979.