For this particular example, Carlos algorithm spits out in < hart beat !
Thanks again Carlos, it will surely help revamp some/many of the GenfitMinimize.

Jean

Levenberg_Marquardt_Code_CBG Copy.sm (65 KiB) downloaded 84 time(s).

Hello Jean,
The same example of the Levenberg Marquardt Algorithm, but obtaining
the Jacobian Matrix through finite differences




Levenberg_Marquardt_Code_CBG_Jean_JMFD.sm (77 KiB) downloaded 76 time(s).


Best Regards

Carlos

Wrote

Hello Jean,
The same example of the Levenberg Marquardt Algorithm, but obtaining
the Jacobian Matrix through finite differences

Thanks, Carlos: works fine.

More doctoring for you !

The work sheet "Otherwise" is only slightly otherwise for convenience, works fine.
The "Jacobian Fails" is another model attempted, Jacobian complains ... Ah !
Same model Pharmacokinetics works fine Conjugate gradient Minimize.
True: some model function can only be fitted by hand
True: GenfitMinimze may be difficult to initialize but work fine for my huge
collection [about 80 projects in Smath].

Cheers ... Jean

Levenberg_Marquardt_Code_CBG Model Otherwise Jacobian FAILS.sm (35 KiB) downloaded 64 time(s).
Genfit Pharmacokinetics.sm (43 KiB) downloaded 69 time(s).
Levenberg_Marquardt_Code_CBG Model Otherwise.sm (53 KiB) downloaded 64 time(s).

Wrote

More doctoring for you !

Jacobian is rescued but does not finish solving
... God does not love Jacob anymore !

Levenberg_Marquardt_Code_CBG Model Otherwise Jacobian NOT calc.sm (39 KiB) downloaded 61 time(s).

Hello Jean
Here is the L-M file that works with your example.

Levenberg_Marquardt_JMFD_CBG.sm (53 KiB) downloaded 67 time(s).




Best Regards

Carlos

Wrote

Hello Jean
Here is the L-M file that works with your example.

Thanks Carlos for doctoring.
By some regrouping, timing dropped from 3.8 min down to 2.6 min.
Niece Smath document for classroom and publishing.
Jean

Genfit Pharmacokinetics L-M Copy.sm (60 KiB) downloaded 65 time(s).

Hi Jean
Another example of the application of the Levenberg Marquardt algorithm,
this time with the Tesla function.



Levenberg_Marquard_Tesla_OK_CBG.sm (546 KiB) downloaded 65 time(s).




Best Regards
Carlos