function secorder3(d);

X = -20:20;
Y = -20:20;
Z = zeros(length(X), length(Y));
for i = 1:length(X)
    for j = 1:length(Y)
        Z(i,j) = norm([X(i),Y(j)],d);
    end
end

figure;
surf(X,Y,Z);
hold on;

X = zeros(50,50);
Y = zeros(50,50);
Z = zeros(50,50);

for i = 1:50
    for j = 1:50
        X(i,j) = -25 + i;
        Z(i,j) = -25 + j;
        Y(i,j) = 0.2*norm([X(i,j),Z(i,j)],d);
    end
end
surf(X,Y,Z);
hold off;
