Eigen values of a Matrix with symbols

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Sankaranarayanan S

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Apr 16, 2014, 12:10:51 PM4/16/14
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I need to find eigen values of matrix with symbols (sx) for the solution of an optimization problem. It seems there is no direct way to do it. numpy.linalg.* does not seem to work for symbolic matrices. Is there anyway to get the eigen values without doing a direct implementation. Thank you

Joel Andersson

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Apr 16, 2014, 12:58:49 PM4/16/14
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Puh... a symbolic expressions for the all the eigenvalues?  Do you need all the eigenvalues or just the largest/smallest one (which can be expressed as a 2-norm)? What does the optimization problem look like and how do the eigenvalues enter? Maybe you can express it as a semi-definite program?

Regards,
Joel

Sankaranarayanan S

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Apr 16, 2014, 1:35:31 PM4/16/14
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Hi Joel,
Thanks for the reply. I just need the maximum Eigen value to find an outer bound which then enters the constraint. I could very well use the 2-norm. Thank you.
Regards,
Sankar

Marco Vaccari

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Mar 31, 2021, 1:25:06 PM3/31/21
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Hi, I came across this old post because I have the same problem that Sankar had. 
Since the norm_2 is used only for vector and norm_fro(A) has no direct relation to the maximum eigenvalue of matrix A, how can I calculate the spectral radius of A (square matrix with SX coefficients?

Thanks,

Marco
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