MATLAB Code for Lagrange Method of Interpolation

Description

Output of Code :

Lagrange Method of Interpolation
***************************Input Data******************************

x array of data:

xdata =

1 0 -2

y array of data:

ydata =

1 1 3
LINEAR INTERPOLATION:

x data chosen: x1 = 1, x2 = 0 , x3 = -2

y data chosen: y1 = 1, y2 = 1 , y3 = 3

The value of x at which y is desired, xdesired = 0.5

Final function =

fl =

(x*(x – 1))/2 – ((x – 1)*(x + 2))/2 + (x*(x + 2))/3

Lagrange weight function values, L0 = 0.416667, L1 = 0.625 , L2 = -0.0416667
The value of f(x) at xdesired, f(0.5) = 0.916667