> There appears to be a few problems here. Try rebasing your year in
> mse, and try using lbfgs directly to compute the lsq estimate
Yes, this works great. Indeed, here we have the same problem with
the initial conditions: if they are not good guesses, lbfgs also
fails (I have checked that, simply write [100,1] instead of
[100,0.01]). But now the procedure to solve this kind of problems
is quite clear. Thank you very much!
By the way, Leo, is nice to have your help here. It's been a long
time since the course on symplectic geometry Omega 99 in Lisbon :)
Cheers,
J. A.