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Mathematica: Eigenvalues for a large symbolic matrix

  1. Jul 13, 2010 #1
    I'm trying to compute the eigenvalues for a 32x32 symbolic matrix (with one variable) in Mathematica. I get the following error:

    Eigenvalues::eival: Unable to find all roots of the characteristic \
    polynomial. >>

    What could be a possible way to proceed?

  2. jcsd
  3. Jul 24, 2010 #2
    Have you tried both Eigenvalues[ ] and Eigensystem[ ]? From which function did you get this error? If it's in one variable then I don't really see why Eigensystem wouldn't work.
  4. Jul 25, 2010 #3
    Try to assume ranges for the constants, i.e. greater than 0, less than 0, etc...
  5. Aug 1, 2010 #4


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    If you are trying to find symbolic expressions for all of the 32 eigenvalues then it is no surprise that it complains. There is no general way to symbolically solve for the roots of a 32nd order polynomial, which is essentially what you are asking it to do. Numerical approaches are of course feasible ....

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