record global stiffness matrix

For developers writing C++, Fortran, Java, code who have questions or comments to make.

Moderators: silvia, selimgunay, Moderators

Post Reply
yen
Posts: 1
Joined: Tue Apr 07, 2009 5:34 am
Location: China

record global stiffness matrix

Post by yen » Tue Apr 07, 2009 6:24 am

Hi Frank,

Now I need to record the global stiffness matrix at every time step. Can you tell me which files need editing?

Thanks,
Yen

fmk
Site Admin
Posts: 5883
Joined: Fri Jun 11, 2004 2:33 pm
Location: UC Berkeley
Contact:

Post by fmk » Thu Apr 09, 2009 11:51 am

you need to pick which SOE you are going to be using. then go to the sourcee code in
OpenSees/SRS/system_of_eqn/linearSOE directory. there are a number of subdirectories. choose the one for the solver you are going to use.

if you download and build the code using CVS you can now add your own solver as a package w/o having to build the rest of the code. there is no doc yet on this as it will not be released officially till the next release due sometime before May 22.

carlos
Posts: 23
Joined: Fri May 05, 2006 8:30 am
Location: Universidad Pais Vasco

Post by carlos » Fri Apr 24, 2009 9:48 am

Hi Frank,

I can imagine from your answer that you are preparing a new version for the Parallel Workshop.

1. Is this new feature of adding external solvers related with Parallel computing or is an indepentent one.?
2. Will you include also additional solvers or we must develop them?.
3. I'm specially would know if this improvement could be used to perform dynamic analysis on free structures, it means, rigid body modes.


I think that it is an interesting option to check complex models. In my opinion, actually one typical error is not to fix properly the model and then it is quite difficult to check the script to see what it is lack.

Regards,

msa_imeg
Posts: 19
Joined: Sun Mar 09, 2008 9:15 pm
Location: Ferdowsi University of Mashhad

Re: record global stiffness matrix

Post by msa_imeg » Fri Apr 24, 2009 8:31 pm

[quote="yen"]Hi Frank,

Now I need to record the global stiffness matrix at every time step. Can you tell me which files need editing?

Thanks,
Yen[/quote]

I do this , I edit FullGenEigenSOE , FE_Element , DOF_Group Classes

I can upload My file if you want !

sjerez
Posts: 2
Joined: Tue Feb 27, 2007 4:08 am
Location: Escuela Colombiana de Ingeniería

Re: record global stiffness matrix

Post by sjerez » Tue Jun 29, 2010 12:36 am

[quote="msa_imeg"]

I do this , I edit FullGenEigenSOE , FE_Element , DOF_Group Classes

I can upload My file if you want ![/quote]

Hello!

I need to get the global stiffness matrix but actually I don't manage quite well the source code. I'm looking into BandSPD to get the A matrix but I would like to see your edited file if possible.
Thanks

Derya Deniz
Posts: 4
Joined: Mon May 04, 2009 9:58 pm
Location: UIUC

Re: record global stiffness matrix

Post by Derya Deniz » Tue Jun 05, 2012 9:32 pm

Hello,
Can somebody please post examples about how to modify the files mentioned above in order to record global stiffness for each time, for any solver? I have checked the files as described above, trying for a long time, but couldn't make it. I really need this. Please, someone help me. Thanks.

sightseeaud
Posts: 1
Joined: Thu Jun 14, 2012 12:53 am
Location: Australia
Contact:

Re: record global stiffness matrix

Post by sightseeaud » Thu Jun 14, 2012 1:03 am

Could everyone share the code?

Cheers!

ilhokan
Posts: 4
Joined: Sun Jul 01, 2012 7:00 am
Location: Boğaziçi University

Re: record global stiffness matrix

Post by ilhokan » Fri Mar 22, 2013 6:15 am

Can someone upload the code required for recording the global stiffness matrix of the model? Now, I am trying to match the SAP2000 Model and OpenSees Model and I got into trouble for obtaining global stiffness matrix for OpenSees Model.

reagan
Posts: 42
Joined: Wed Oct 26, 2011 5:54 pm
Location: Stanford University

Re: record global stiffness matrix

Post by reagan » Thu Feb 27, 2014 12:52 am

Hi Frank

Just wanted to check if there are any updates to this thread. By any chance has functionality been added to OpenSees to view the Mass / Stiffness matrices?

My model's producing some complex eigenvalues and I'd like to see what's going on by looking at the matrices.

Thanks

Reagan

fmk
Site Admin
Posts: 5883
Joined: Fri Jun 11, 2004 2:33 pm
Location: UC Berkeley
Contact:

Re: record global stiffness matrix

Post by fmk » Thu Feb 27, 2014 8:34 am

new command to print the contents of the A matrix (printA) that only will work with a full matrix, i.e. system FullGeneral

http://opensees.berkeley.edu/wiki/index ... tA_Command

radmard
Posts: 9
Joined: Mon Jun 22, 2015 11:51 am
Location: Bauhaus University

Re: record global stiffness matrix

Post by radmard » Tue Dec 22, 2015 3:30 am

PrintA does not work after analyze command in a static analysis. ( system FullGeneral is used).
No file be created.
Any suggestions or same experience?

fmk
Site Admin
Posts: 5883
Joined: Fri Jun 11, 2004 2:33 pm
Location: UC Berkeley
Contact:

Re: record global stiffness matrix

Post by fmk » Tue Dec 22, 2015 5:22 am

are you using the latest version? try this:

wipe
model Basic -ndm 2
node 1 0. 0.
node 2 0. 1.
fix 2 1 1 1
geomTransf Linear 1
element elasticBeamColumn 1 1 2 100 100 100 1
integrator LoadControl 1.0
system FullGeneral
analysis Static
analyze 1
printA -file tmp.out

Post Reply