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From: Yanlong Yang on 20 Apr 2007 00:59
I have a 64*64 complex Matrix ,and want to find some of the eigenvalues
lamda whose log has a very small imaginary part


lamda=eig(U);
b=-i*log(lamda)

imag(b) = 1e-25 or so
Does Matlab (core 2 due ,windows xp sp2 32bit) can give me the correct
result?

On my pc,the eps= 2.2204e-016,and I got the most small eigenvalues on
the order of 1e-16.

I have tried the symbolic toolbox,but the extremely slow speed made me
gave up.

Must I install a 64 bit version of windows or Linux to get the correct
eigenvalues?

(An another example ,if eps=2.22e-16,A=[1 eps;eps 1],how to get the
true eigenvalues 1+eps,1-eps on the order of 1e-17 or more precisions
withhout symbolic toolbox?)

Thanks in advance.
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