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 Dear Jena, Yes, this is quite standard to consider an absolute maximum residual proportional to a RHS norm. However, the residual considered in the standard solve in GetFEM is already a relative residual, which means that the maximal residual given to the standard solve is already multiplied by an estimate of the total load. Best regards, Yves Le 09/05/2019 à 08:44, Moritz Jena a écrit : Hello Yves, Thanks for your quick answer. Adapting the residuum at each iteration step is very interesting and I will try to implement this in my code. However, my problem is still, to determine/calculate the maximum allowed residuum depending on my model. At the moment I follow the theory, that the maximum allowed residuum max_res is calculated with respect to the external forces: If external_forces > 1e-5 * 1000        max_res = external_forces / 1000 else        max_res = 1e-5 end I base my theory on observations in ansys. Am I right with my theory? Or is there even another (maybe easier) way to get a plausible max_res out of GetFEM? Best regards, Moritz Jena Von:        Yves Renard An:        Moritz Jena Kopie:        getfem-users Datum:        08.05.2019 17:11 Betreff:        Re: [Getfem-users] Maximum allowed residuum Dear Jena, Unfortunately, from the interface you cannot adjust the maximum residual and change it from a Newton sub-iteration to another. The only mean I see from the interface is to call for only one Newton iteration each time, then change the maximum residual from a call to another and loop until the convergence criterium is not reached. Best Regards, Yves ----- Mail original ----- De: "Moritz Jena" À: "getfem-users" Envoyé: Mardi 7 Mai 2019 16:23:00 Objet: [Getfem-users] Maximum allowed residuum Dear GetFEM-Users, I have written a FEM program, with which you can calculate technical springs numerically. Therefore I'm using the GetFEM-MATLAB-Interface 4.3 These calculations are highly non-linear due to self-contact issues and large deformations. That is the reason why technical springs have to be solved iteratively in several substeps. The calculation by itself works very well. But I think I have a problem with the maximum allowed residuum that is passed to the solve command of getfem. My theory is that the maximum allowed residuum has to be variable during the different substeps. By investigating these question online I found a paper of an university in Germany that contains the following for a equation system of A*x=b : ||delta_x||/||x|| <= Cond(A) * ||delta_b||/||b|| Unfortunatley these _expression_ is not leading to plausible results. I'm also familiar using ansys. By using this commercial software I know that the maximum allowed residuum is changing by each iteration and by each substep. All of the delivered getfem examples are using a constant maximum allowed residuum, no matter of high deformation or not. So my question is, how am I able to find the maximum allowed residuum and by what _expression_? And do I have to define a variable maximum allowed residuum during the substeps to get reliable results out of the solve command? Best regards, Moritz Jena ```-- Yves Renard (address@hidden) tel : (33) 04.72.43.87.08 INSA-Lyon 20, rue Albert Einstein 69621 Villeurbanne Cedex, FRANCE http://math.univ-lyon1.fr/~renard --------- ```