UNIFORMLY HIGHER ORDER ACCURATE EXTRAPOLATIONS TO SOLUTIONS OF UNIFORMLY CONVERGENT DISCRETIZATION METHODS FOR SINGULARLY PERTURBED PROBLEMS

摘要

We discuss the uniformly higher order accurate extrapolations,which are based on theuniform expansion for global error,to solutions of uniformly convergent discretizationmethods for singularly perturbed problems.By applying the approach to the Il’in-Allen-Southwell scheme for a non-self-adjoint problem,we obtain an extrapolation solution whichis uniformly convergent with order two.We confirm the result by numerical calculations.