Parameter command for response variables.

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lorcancon
Posts: 25
Joined: Thu May 22, 2014 5:22 am
Location: Roughan & O Donovan

Parameter command for response variables.

Post by lorcancon »

All,

I have managed to assign nodal displacements to a parameter using the following command:

parameter $paramtag node $nodetag disp $DOF

However, I was wondering what other response variables can be assigned to parameters, and what their commands are. For example, how does one assign an internal element force (e.g. axial force) to a parameter? I think this should be possible because a method is given in the paper: "Summary of Work on OpenSees Reliability/Optimization/Sensitivity (2012)". However, the commands in this paper seem to be out of date. Is there a more up-to-date version of this paper? Could you reference me to the section of the source code which relates to assigning parameters to node /element responses?

Thanks in advance,
Lorcan.
fmk
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Re: Parameter command for response variables.

Post by fmk »

basically you want to look for a setParameter() in the source code for a class (element, material, node, ...) to see if something in it can be updated using the parameter commands .. the updateParameter() is the code that is actually called when the parameter needs updating.
lorcancon
Posts: 25
Joined: Thu May 22, 2014 5:22 am
Location: Roughan & O Donovan

Re: Parameter command for response variables.

Post by lorcancon »

Frank,

Thanks for your response. I've been looking through the source code and it's easy to see the set parameter() commands for each class for class properties (area, stiffness, geometric properties etc.). However, the set parameter() commands for class responses (nodal displacements, element loads etc.) seems to be stored in a different location, which I cannot find. Let me give you an example of what I'm looking for...

In the command:
parameter $paramtag node $nodetag disp $DO
the command "disp" represents a nodal response which can be assigned to a parameter...

In an attempt to assign a parameter to an axial load, I am looking for a command like:
parameter $paramtag element $eletag "forces???" $forcenumber
I have tried the command "forces" as this is the command for recording element resisting forces, and I assume some similar command exists for assigning resisting forces to parameters. However, this has not worked and I cannot find the section of the source code which relates specifically to assigning resisting forces to parameters.

Thanks again,
Lorcan.
lorcancon
Posts: 25
Joined: Thu May 22, 2014 5:22 am
Location: Roughan & O Donovan

Re: Parameter command for response variables.

Post by lorcancon »

Apologies, there is an error in my last comment. The command relating parameters to nodal displcement should be:

parameter $paramtag node $nodetag disp $DOF
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