function Lnf = lagrange_classic(nodes,f_nodes,x)
  n = length(nodes);
  m = length(x);
  Lnf = zeros(size(x));
  l = zeros(size(nodes));
  for i = 1:m
    for j = 1:n
      l(j) =(prod( x(i) - nodes([1:j-1,j+1:n])))/(prod( nodes(j) - nodes([1:j-1,j+1:n])));
    endfor
    Lnf(i) = l*f_nodes';

  endfor
end;