Dear Getfem users,
i have quite a broad question about the calibration of parameters related to the line search in the solve method
I am trying to solve a collection of 3D problems that involve hyperelasticity, unilateral contact and friction. In a 2D case, i could manage without it but in 3D, it seems slightly more complicated and i hope some insight regarding the line search could help the convergence (i am using multipliers for the contact and playing with the augmentation parameter did not help).
For instance, according to the documentation, there are 4 methods available:
select explicitely the line search method used for the linear systems (the default value is ‘default’). Possible values are ‘simplest’, ‘systematic’, ‘quadratic’ or ‘basic’.
Could you describe the differences between these methods? In which context should I rather use one instead of another?
In previous discussions, there were some examples, here is one
model.solve('max_res', 1E-5, 'noisy','max_iter',60, 'lsolver', 'MUMPS',
'lsearch', 'simplest', 'alpha max ratio', 1.5, 'alpha min', 0.2,
'alpha mult', 0.6)
Are
alpha max ratio,
alpha min
and
alpha mult
the only parameters we have control over, for a given line search method? Are the other relevant? Do you have some advices regarding the choice of these parameters?
and that is quite useful to some extent but some help would be more than welcome, in particular related to "user experience".
Thanks in advance,
David