% Lagrange polinom x = [2 2.25 2.5 2.75] y = [3 55/16 5/2 -3/16] % gyoktenyezok p1 = [1 -2] p2 = [1 -2.25] p3 = [1 -2.5] p4 = [1 -2.75] % Lagrange segedpolinomok l1 = conv(conv(p2,p3), p4); l1 = l1/polyval(l1,2) l2 = conv(conv(p1,p3), p4); l2 = l2/polyval(l2,2.25) l3 = conv(conv(p1,p2), p4); l3 = l3/polyval(l3,2.5) l4 = conv(conv(p1,p2), p3); l4 = l4/polyval(l4,2.75) % Lagrange poli L = y(1) * l1 + y(2) * l2 + y(3)*l3 + y(4)*l4 % abra t = 1:0.1:4; plot(t,polyval(L,t),x,y,'*')