Algorithm 1.

A Python version of Newton's method for a generic function f = F and its derivative fp = F′ to find the point t^*such that f(t^*) = 0. In our case F and F′depend on the fitted parameters τ_r, τ_f, τ_s, I_f, and I_s.

def Newton(t_in, f, fp, TOL, MaxIter)

t = t_in;

d = 1;

niter = 1;

while abs(d)>TOL && niter < =MaxIter:

d = f(t)/fp(t)

t -= d

niter += 1

return t