So I generated a decay of some data using this code, and the decay works! But now I am trying to fit it into a biexponential fit. I have this code, but it is not working for some reason. Does anybody know what I should do?
Decay code (works):
Biexponential fit code (does not work):
ft = fittype('exp2');
ft(a,b,t1,t2,x) = a*exp(b*x) + t1*exp(t2*x);