M. Arad et al., HIGH-ORDER-ACCURATE DISCRETIZATION STENCIL FOR AN ELLIPTIC EQUATION, International journal for numerical methods in fluids, 23(4), 1996, pp. 367-377
The coefficients for a nine-point high-order-accurate discretization s
cheme for an elliptic equation del(2)u - gamma(2)u = r(0) (del(2) is t
he two-dimensional Laplacian operator) are derived. Examples with Diri
chlet and Neumann boundary conditions are considered. In order to demo
nstrate the high-order accuracy of the method, numerical results are c
ompared with exact solutions.