eigen value analysis for higher order schemes
 

Hi,

I am performing an eigen value analysis for a higher order spectral volume-like scheme. Since there are multiple degrees of freedom, I get a set of eigen values (same as DOF) corresponding to the eigen modes. Now, how do I sort those eigen values such that they correspond to a particular mode? I use octave for these computations. The eigen values it provides are not sorted correctly. That is, if I plot the eigen values for a range of wave number (0-pi), I get discontinuous plots. Is there a way to sort the eigen values as per the modes?

Regards, Shyam