input parameters from matlab

[Alexandros]

Hi
in my work i need to call opensees through matlab. Althought i know how to do that (! Opensees.exe scriptname.tcl
) i do not know how to call my input parameters for opensees through matlab. For example i input a load in matlab and then i need opensees to use this value.

Thank you in advance

[hugo_esquivel]

If you are working on an unix-based system, then you can link matlab with opensees by using a fifo pipe... e.g. open two shells (I am using two bash shells here for simplicity)...

On shell #1, write:
% mkfifo pipe # creates a pipe file.
% echo "This message will be sent to shell #2" > pipe

On shell #2, write:
% cat < pipe
to display on screen the message sent from shell #1.

google: fifo unix for more information.

Hope it helps.

[Alexandros]

Thank you for your reply.
I ll try to do that. I am familiar with unix but i do not use it that much.
Is there any other way to do it on windows system?

[hugo_esquivel]

I once read that the same thing could not be done on a windows system. But you might want to check the veracity of that statement since I am not entirely sure about it.

[claytp]

What I have done (which is not nearly as sophisticated as the previous suggestion) is to use matlab to create my .tcl script using the input parameters from matlab. Then, run that script from matlab using the !OpenSees.exe command.

For example, when I create a recorder file in matlab:
fid = fopen('recorders.tcl', 'wt')
fprintf(fid, 'recorder Node -file $dataDir/DFree.out -time -dT $dTrec -node %4.0f %4.0f -dof 1 2 3 disp; \n' , freeNodes)
... lots more fprintf lines
fclose(fid)

then call "recorders.tcl" in my main .tcl model script that i will run.

[Alexandros]

Thank you very much

that's exactly what i was thinking today.
Its not the most efficient way but maybe its the only way for windows.

[khansoltani]

When I call OpenSees from a Matlab script, I face this error:

invalid command name "pattern"

While running the same code (pattern Plain 1 Linear {...}) just through the Opensees works correctly.
How can I fix it?

Thank you in advance

[selimgunay]

It may be a compatibility issue due to Matlab version. Generally running OpenSees from Matlab would slow down the analysis. A better approach is to create all the loops in tcl and run different cases directly using the for loops in tcl.