Cervenka Consulting Forums — BFGS Method

Re: BFGS Method

null@example.com (dpryl) — Mon, 04 Jan 2016 13:56:15 +0000

And, of course, if you do not succeed localizing the problem source, you can send us your model etc. following Troubleshooting, 2.1.1.

Re: BFGS Method

null@example.com (dpryl) — Mon, 04 Jan 2016 09:23:23 +0000

Hello myforework,
no, that method is not implemented in ATENA. However, according to our experience, in most cases, convergence issues are a consequence of some problem(s) in the modelling (from such trivial as missing supports to more complicated ones which are not so obvious), see also ATENA Troubleshooting, 2.4.2 I get the message "The execution is killed due to violation of stop iteration criteria", what does it mean?, 2.4.6 Floating point problems - Division by zero, Loss of >7 digits on the matrix diagonal, CCFEModelExc: CCPardiso solver error: zero pivot, Warning: Sign of diagonal changed when reducing equation, Floating point exception: Multiple floating points traps, Zero or negative jacobian, InvertA: zero determinant, CCMaterials Extended AExc: CC5ParamYield F: project_stress_on_f_division by zero, and similar, 2.1.19 Problems reaching convergence and understanding ATENA convergence parameters, and 2.2.22 How to detect a structural collapse or ultimate load capacity.

However, I am noting BFGS (or more likely some of its limited memory variants) to the list of ideas for possible future development.

Regards.

BFGS Method

null@example.com (myforework) — Mon, 04 Jan 2016 00:32:15 +0000

Hello,

I find my problem is really hard to converge, while I am using other software it converged by using BFGS method. is BFGS method currently implemented in ATENA? or is there any tips to solve it? I've tried some changes in the Analysis parameter options but still couldn't find away.
the first and second step it's converged pretty fast, but from 3rd to 5th (last step) it doesn't converge although the iteration is finished up to the maximum number of iteration.

Thank you