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mhscott wrote: > You are getting negative eigenvalues ... check your model!!! Dear mhscott, I do know this message comes out because of the "negative eigenvalue". I have checked my model for three days and times and times again. I tried every constraints command and eigen command in my mod...

To anyone kind enough to help me, I am trying to simulate a 1-story, 2-bay RC frame specimen. I have built the model and when I try to do the dynamic EQ analysis, but it just showed "domain error: argument not in valid range" and stopped. Here is my model: # SET UP ------------------------...

mhscott wrote: > You must have negative eigenvalues. Check your model's boundary conditions > and element connectivity. Dear Professor mhscott, I used "constraints Transformation" when I got the problem I mentioned above. When I tried "constraints Lagrange", Opensees showed numbe...

mhscott wrote: > You must have negative eigenvalues. Check your model's boundary conditions > and element connectivity. Thanks for your reply! I thought it may be this reason, but I do not know how to fix it. Could you please tell me which command I should check? I fix my three support nodes by &quo...

I am trying to simulate a 1-story, 2-bay RC frame experiment. I have built the model and when I try to do the dynamic EQ analysis, it can not run successfully. I wrote some "Puts" between my code, so I figured out that "Rayleigh Damp" might be the problem. But I don't konw how to...