Preservation of stability properties near fixed points of linear   hamiltonian systems by symplectic integrators
  Based on reasonable testing model problems, we study the preservation by symplectic Runge-Kutta method (SRK) and symplectic partitioned Runge-Kutta method (SPRK) of structures for fixed points of linear Hamiltonian systems. The structure-preservation region provides a practical criterion for choosing step-size in symplectic computation. Examples are given to justify the investigation. 
Xiaohua Ding, Hongyu Liu, Zaijiu Shang, Geng Sun, Lingshu Wang