% Section 3.1, problem 6(a) format long x=[ 0 0.25 0.5 0.75]; y=[ 1 1.64872 2.71828 4.48169]; xstar = 0.43; n = length(x)-1; Q = zeros(n+1); Q(:,1) = y'; R = Q; for i = 1:n for j = 1:i Q(i+1,j+1) = ( (xstar-x(i-j+1))*Q(i+1,j) - (xstar-x(i+1))*Q(i,j) ) ... /( x(i+1)-x(i-j+1) ); end end Q(n+1,n+1) for j = 1:n for i = n:-1:j R(i+1,j+1) = ( (xstar-x(i-j+1))*R(i+1,j) - (xstar-x(i+1))*R(i,j) ) ... /( x(i+1)-x(i-j+1) ); end end R(n+1,n+1)