** Complex diagonal form to real block diagonal form. **

** [V,D] = CDF2RDF(V,D) transforms the outputs of EIG from complex **

** diagonal form to a real diagonal form. In complex diagonal form, **

** D has complex eigenvalues down the diagonal. In real diagonal **

** form, the complex eigenvalues are in 2-by-2 blocks on the **

** diagonal. Complex eigenvalue pairs are assumed to be next **

** to one another. **

** **