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Eigenvectors and eigenvalues

May 6, 2013 at 10:57 AM
Hi,
First of all, thank you for your wonderful piece of software! I am using it for a project of mine. I have to find eigenvalues and eigenvectors for asquare 50x50 matrix (sorry, I cannot attach it, please tell me how I can provide it). In my laptop Intel(R) Core(TM)2 Duo (32-bit) I obtain all eigenvalues, but not all eigenvectors (in particular, rows and columns 1, 8, 11, 47 of the corresponding ComplexEigensystem.Eigenvector object have Re=NaN, Im=NaN). This does not happen with another computer (I do not have the characteristics, but I know it is 64-bit), in which everything goes fine.
Can you help me to find the problem?
Thank you in advance,
Corrado
May 6, 2013 at 2:42 PM
Hi,
I could solve the problem replacing the complex eigensystem with a real eigensystem, for my matrix was symmetric. Though, the problem could be of interest because it is likely to be a bug in ComplexEigenSystem class.
Best regards,
Corrado
May 6, 2013 at 9:21 PM
Thanks so much for your report. Via your codeplex contact page, I have sent you an email address to which you can send the problematic matrix. I'd be very interested to try to identify the issue; the fact that you see different behavior on 32-bit and 64-bit machines is unexpected and intriguing.