  We present a new algorithm for computing the Lyapunov exponents spectrum
based on a matrix differential equation. The approach belongs to the so called
continuous type, where the rate of expansion of perturbations is obtained for
all times, and the exponents are reached as the limit at infinity. It does not
involve exponentially divergent quantities so there is no need of rescaling or
realigning of the solution. We show the algorithm's advantages and drawbacks
using mainly the example of a particle moving between two contracting walls.
