Is it possible to output the stiffness and mass matrix in Sofistik?


I am a master student and now I am working on my Thesis (Structure dynamics).
So, I need plotted stiffness and mass values of structure model.

Аccordingly the question is, how can I get the stiffness and mass values ?
Is there any technique to output those values using Teddy commands ?

Hello Nuku,
If you want to use Teddy Input Language (CADINP) we provide several examples to all kind of topics, also dynamics.
For eigenfrequency you can have a look at the example ase4_eigenfrequencies.dat at Teddy - Data - Examples - ASE - english - ase4…
For earthquake analysis you can have a look at ASE - English - dynamics - earthquake_jb.dat
If you want to use modul DYNA, you can have a look at DYNA - english - storeys - storeys.dat using response spectrum analysis.
If you are not sure, which modul is the way to go, please have a look at our manuals regarding ase and dyna, you can find them at Teddy/SSD - Help - Manuals - All Manuals e.g. ASE p. 2-85 Chap. 2.15
Using ASE you get a quick eigenvalue analysis (Command EIGE), you can have a look at the results and eigenvalues at the report browser.

Tutorial using SSD:

Hope these informations will help

Best regards,
Your SOFiSTiK Support Team

Thank you NAL for extended explanations,
there were very useful information.

But, I couldnt find any way to output stiffness matrix or mass matrix (SM or MM) of the system of structure at those manuals and examples. For example, Sap2000 has features to output SM or MM converted to text files. I cant believe that there are no ways to display these values in Sofistik.

There should be a possibility within CADINP. I remember reading some values in the CDBASE(Database). You can read through the CDBASE Help. Maybe you’ll find something there. (Help-Ribbon -> CDBASE-Help)
With @KEY you can get access to the data in your code to read them in.

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Thank you ebassti,

I will try CDBase extraction with @Rec: 175/00

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I couldnt extract stiffness matrix of entire system of structure with @key S_MATRIX. An error window appears.
Most likely this is due to the fact that I did not correctly specify the command.

Below are the commands I used (after linear and dynamic calculations of system):

+prog template
head Smatrix
@cdb example1

Please, help me…


I’m not quite sure how this works exactly, but you could try my suggestions.
It may be, that it’s only possible for single elements though.

at means @


or how I used this for displacement values before:

atKEY S_MATRIX #number_of_element
let#K at1101 (or at101)

Thank you,
I get stiffness matrix only for 1 element, but not for entire system (global stiffness matrix).
I think there is no possibility for output entire system stiffness matrix

Hello Nuku,

I am also trying to obtain the stiffness matrix of the global system or a single element. How did you obtained the stiffness matrix of one element?


Hello Nuku,

I’m a student in civil engineering and I would like to get the stifness matrix for 1 element too. Can you please exhibe the solution ?


If I’m not mistaken you can’t get the stiffness matrix for an arbitrary element through the cdb.

If there is an element under record 175/00 it has been generated manually. I.e. with ADDM or FLEX in SOFIMSHA.
→ The entire matrix has ben input by the user, so the contents should already be known.