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Extracting Eigenvalues and Eigenvector using Eigenfrequency study
Posted Nov 30, 2014, 3:22 p.m. EST Structural Mechanics Version 4.4 2 Replies
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Hello,
I was successfully able to extract the first N (~ 50) eigenvalues, using Eigenfrequency study and Solid Mechanics physics setup. I use the export option to write out the frequencies and eigenvalues (lambda).
However, now I also need the corresponding Eigenvectors. I am not able to do the same, since the exporter does not show Eigenvectors in the export list.
Pls let me know how I can export the first N eigenvalue and eigenvectors pairs. Is there is a simpler way to do this using Matlab LiveLink?
Thanks,
Gaurav
I was successfully able to extract the first N (~ 50) eigenvalues, using Eigenfrequency study and Solid Mechanics physics setup. I use the export option to write out the frequencies and eigenvalues (lambda).
However, now I also need the corresponding Eigenvectors. I am not able to do the same, since the exporter does not show Eigenvectors in the export list.
Pls let me know how I can export the first N eigenvalue and eigenvectors pairs. Is there is a simpler way to do this using Matlab LiveLink?
Thanks,
Gaurav
2 Replies Last Post Dec 3, 2014, 8:31 a.m. EST
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Posted:
10 years ago
Could someone pls answer. I have seen posts (e.g. www.comsol.com/community/forums/general/thread/31634/) where people talk about having Eigenvectors data access, but am not sure how they actually extract it from COMSOL.
Thanks,
Gaurav
Thanks,
Gaurav
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Posted:
10 years ago
Hi,
You should be able to select displacements in the Expressions section of Results->Export->Data. If you do not find them in the list, you can always write u, v and w explicitly in the list of expressions.
Which physics interface (element type) are you using? If it is 'subdimensional' (like a shell which lives on surfaces in 3D) you may have to do a manual selection for 'Geometry Level' in Results->Export->Data.
Regards,
Henrik
You should be able to select displacements in the Expressions section of Results->Export->Data. If you do not find them in the list, you can always write u, v and w explicitly in the list of expressions.
Which physics interface (element type) are you using? If it is 'subdimensional' (like a shell which lives on surfaces in 3D) you may have to do a manual selection for 'Geometry Level' in Results->Export->Data.
Regards,
Henrik