fitting a function with 3 parameter

Hello everyone;

I have some data include x,y,z,t.

how can I fitting this data on this Equation: t= a*x+b*y+c*z

i need a,b,c .

Answer 1

[Bjorn Gustavsson]

This is a simple linear fitting problem, you solve it this way:

M = [x(:),y(:),z(:)]; % creating a matrix of all your independent parameters giving you a 
                      % vector-matrix-versio of your equation:
                      % t = M*abc(:);
abc = M\t;

You can generalize this for arbitrary fitting-functions, just expand M with columns for x^2, sin(w*y) and the like. Matlab has all sort of fitting functions more general and agile. Have a look at polyfit, lscov and others

HTH