This program represents a further development of the standard powerful “nlinfit” facility already in matlab. The major problem with “nlinfit” is that it can only handle fitting of one dimensional arrays (x, y) where x is the independent variable and y is the dependent one.
The program fit2 uses another program “fitfit” where the user fitting function can be defined. This user defined function is defined in line 6 of fitfit as ff in terms of a,x,y.
The input arguments to the program are
1- a which is an array representing the starting values of the free
fitting parameters ( similar to that when nlinfit is used)
The length of a must be equal to the number of parameters used in the user
defined function to be fitted (line 6 in the M-file "fitfit"
2- x and y are each a one dimensional array representing the independent
3- z is the dependent variable matrix whose elements are functions of the
meshgrid values of x and y
please read the pdf file for more information and example