As the input data I have three arrays: X contains the x-coordinates, Y contains the y-coordinates and Z is the function of the first two coordinates, Z = f(X,Y).
The code is here:
X = [0 1 5 4 2 5 0 5 3];
Y = [0 3 2 6 6 1 2 12 2];
Z = [500 440 300 580 410 800 700 400 700];
I know the way to interpolate using these points. I used griddata and it was okay. But now I need to create a symbolic expression with MATLAB. I read about polyfit and feval but still don't really understand from what I should start and how to build an interpolational function z = f(x,y). Is there any way to make, for example, bicubic interpolation?
As the output I wanna get a symbolic expression.
I would appreciate any help because I'm really interested in it