system command

[khosravifar]

Does anyone have a good reference on how to choose the best option for system, numberer and algorithm commands?

My model includes soil, structure and soil spring elements and I have been doing that mostly by try and error so far, but I was wondering if someone has done this in a more systematic way (probably by looking at the stiffness matrix, maybe?)

[fmk]

if it's a lerge model you will be best with a sparse solver, for which you need just the plain numberer as they all reorder.

for small problems choose the band or profile solver and look at RCM and SMD.

i cannot tell you how large it has to be before you ned to switch, it depnds on your model, materials and the computer you are running on.

as for the algorithm, I use Newton and in the script try other things if it fails BUT go back to Newton after that step. some people also like NewtonLineSearch. for a nonlinear analysis you will probably find that you cannot do all steps with just one choice of algorithm.

[Cokykils]

[quote]if it's a large model you will be best with a sparse solver, for which you need just the plain numberer as they all reorder. for small problems choose the band or profile solver and look at RCM and SMD. i cannot tell you how large it has to be before you ned to switch, it depnds on your model, materials and the computer you are running on. as for the algorithm, I use Newton and in the script try other things if it fails BUT go back to Newton after that step. some people also like NewtonLineSearch. for a nonlinear analysis you will probably find that you cannot do all steps with just one choice of algorithm.[/quote]

[Vinashin]

There are different type of System commands for different type of software.I am talking about C++ Program here. I am learning C++ Language and i have known lot of abut language cording that is very useful for my course..
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