clear all %clc format long n=4; f=@(x) x-exp(-2*x); x=f(0.45); xfx=[0,0.3;0,0.4;0,0.5;0,0.6]; for l=1:n xfx(l,1)=f(xfx(l,2)); end q=zeros(n,n); q(:,1)=xfx(:,2); for i=2:n for j=2:i q(i,j)=(q(i,j-1)*(x-xfx(i-j+1,1))-q(i-1,j-1)*(x-xfx(i,1)))/(xfx(i,1)-xfx(i-j+1,1)); end end q(n,n) f(q(n,n))