School/Anul 3/Semestrul 2/Calcul numeric/backsub.m

function x = backsub(U, b)
    n = length(b);
    x = zeros(size(b));
    for k = n:-1:1
      x(k) = (b(k) - (U(k,k+1:n) * x(k+1:n)))/U(k,k);
    endfor
end;