Eigenvalue order
I notice that Sage orders A.eigenvalues() from lowest to highest (ascending order). Where does this functionality come from? Is NUMPY used in the backend?
I am trying to understand how to diagonalize a real symmetric matrix A with orthogonal Q such that QTAQ=D where D is diagonal and always in a specific order (say ascending or descending).
The ordering of the eigenvalues has a meanoing if and only if all these values belong in a "reasonably ordered" set. What do you think of complex eigenvalues ? and what about :
HTH,