Lyapunov Exponents without Rescaling and Reorthogonalization
  We present a new method for the computation of Lyapunov exponents utilizing representations of orthogonal matrices applied to decompositions of M or MM_trans where M is the tangent map. This method uses a minimal set of variables, does not require renormalization or reorthogonalization, can be used to efficiently compute partial Lyapunov spectra, and does not break down when the Lyapunov spectrum is degenerate. 
Govindan Rangarajan, Salman Habib, and Robert D. Ryne