A = (-0.5, 3.74)
B = (0.68, 4.4)
C = (3.48, 2.48)
D = (5.76, 2.28)
f = LagrangeInterpol4(A, B, C, D)

Tool: Lagrange Interpol 4 (command LagrangeInterpol4)
4 Punkte anklicken
Input: A, B, C, D
Output: lagrinterpol

l1(x) = (x - x(B)) / (x(A) - x(B)) * (x - x(C)) / (x(A) - x(C)) * (x - x(D)) / (x(A) - x(D))
l2(x) = (x - x(A)) / (x(B) - x(A)) * (x - x(C)) / (x(B) - x(C)) * (x - x(D)) / (x(B) - x(D))
l3(x) = (x - x(A)) / (x(C) - x(A)) * (x - x(B)) / (x(C) - x(B)) * (x - x(D)) / (x(C) - x(D))
l4(x) = (x - x(A)) / (x(D) - x(A)) * (x - x(B)) / (x(D) - x(B)) * (x - x(C)) / (x(D) - x(C))
lagrinterpol(x) = y(A) * l1(x) + y(B) * l2(x) + y(C) * l3(x) + y(D) * l4(x)