I have a Matrix. The colums represent the X values and the rows represent the Y values and the matrix element Z represents the value at (X,Y). So, in my case, X runs from 1 to 250 and Y runs from 1 to 3500. I would like to fit an equation (I suspect that the data is going to be of high order *say 50) so maybe spline?) such that Z=f(X,Y) where Z is the matrix element
Say I choose X=10 and Y=2300 in the matrix. The matrix will have a particular value Z (say 30000) at (10,2300). Now I want to fit a equation for Z as a function of X and Y. What do I do?