A new block method for computing the Hamiltonian Schur form

A generalization of the method of Chu et al. [D. Chu, X. Liu, V. Mehrmann, A numerical method for computing the Hamiltonian Schur form. Numer. Math. 105 (2007) 375–412]. for the computation of the Hamiltonian real Schur form is presented. The new method avoids some of the difficulties that may arise when a Hamiltonian matrix has tightly clustered groups of eigenvalues. A detailed analysis of the method is presented and several numerical examples demonstrate the superior behavior of the method.