Greetings! Matlab has a function `ordeig` that computes the eigenvalues of a real quasi-triangular matrix (may have 2x2 blocks on the diagonal, corresponding to complex conjugate eigenvalues) in the order in which they appear in the matrix. This is particularly useful in conjunction with `ordschur`, since one often wants to write something like `ordschur(Q, T, abs(ordeig(T)) .< 1)` to bring in leading position the eigenvalues inside the unit circle.
Julia does not have `ordeig`, and I suppose that there is no specialized implementation of `eig` for quasitriangular matrices (since `schur` returns them as `Array{Float64,2}`, without a custom type). So I suppose that there are no guarantees on the ordering of eigenvalues. Is all of this correct? If so, there is no hope of being able to use the above idiom with `ordeig`, and the only way to get it working is by computing the ordered eigenvalues of `T` by hand. Thanks, -federico