clear all exact_vlue=2/3; for n=[17 33 65 129 257 361 1025 4001 40001 400001] % n must be odd h=1/(n-1); x=linspace(0,1,n); y_h=(x).^(1/2); y_2h=(x(1:2:end)).^(1/2); tra_h = (h/2)*(y_h(1) + 2*sum(y_h(2:1:end-1)) + y_h(end)); tra_2h = (h)*(y_2h(1) + 2*sum(y_2h(2:1:end-1)) + y_2h(end)); p1=log2((exact_vlue-tra_2h)/(exact_vlue-tra_h)); fprintf('n = %9d , h= % 1.7f , p1 = %1.7f\n',n,h,p1) end