classdef D4Periodic < sbp.OpSet
    properties
        norms % Struct containing norm matrices such as H,Q, M
        boundary  % Struct contanging vectors for boundry point approximations
        derivatives % Struct containging differentiation operators
        borrowing % Struct with borrowing limits for different norm matrices
        m % Number of grid points.
        h % Step size
    end



    methods
        function obj = D4Periodic(m,h,order)

            if order == 2
                [H, HI, D1, D4, e_1, e_m, M4, Q, S2_1, S2_m, S3_1, S3_m, S_1, S_m] = sbp.higher2_compatible(m,h);
                obj.borrowing.N.S2 = 0.7500;
                obj.borrowing.N.S3 = 0.3000;
            elseif order == 4

                [H, HI, D1, D4, e_1, e_m, M4, Q, S2_1, S2_m, S3_1, S3_m, S_1, S_m] = sbp.higher4_compatible(m,h);
                obj.borrowing.N.S2 = 0.4210;
                obj.borrowing.N.S3 = 0.7080;
            elseif order == 6
                [H, HI, D1, D4, e_1, e_m, M4, Q, S2_1, S2_m, S3_1, S3_m, S_1, S_m] = sbp.higher6_compatible(m,h);
                obj.borrowing.N.S2 = 0.06925;
                obj.borrowing.N.S3 = 0.05128;
            else
                error('Invalid operator order.');
            end

            obj.h = h;
            obj.m = m;

            obj.norms.H = H;
            obj.norms.HI = HI;
            obj.norms.Q = Q;
            obj.norms.N = M4;

            obj.boundary.e_1 = e_1;
            obj.boundary.S_1 = S_1;
            obj.boundary.S2_1 = S2_1;
            obj.boundary.S3_1 = S3_1;

            obj.boundary.e_m = e_m;
            obj.boundary.S_m = S_m;
            obj.boundary.S2_m = S2_m;
            obj.boundary.S3_m = S3_m;

            obj.derivatives.D1 = D1;
            obj.derivatives.D4 = D4;

        end
    end

    methods (Static)
        function lambda = smallestGrid(obj)
            error('Not implmented')
        end
    end



end