"Bruno Luong" <firstname.lastname@example.org> wrote in message <email@example.com>... > "Matt J" wrote in message <firstname.lastname@example.org>... > > > f(x)=(sqrt(F(x)-f_low))^2 > > What you write is > > f(x) = abs(F(x)-f_low) = F(x)-f_low > > Minimizing f(x) is the same as minimizing F(x). How far do we get? ===============
That should really have been
But yes, the above is equivalent to minimizing F(x). That's what we want. Now, however, you can feed f(x) to LSQNONLIN and run its Levenberg-Marquardt routine.