  We use a scheme of separation of degrees of freedom for a system, in order to
produce two systems with finite number of degrees of freedom. Our intent is to
measure the energy square relative fluctuation (SRF) of the observable part
through the simulation of two simple examples of composed systems, the harmonic
oscillator, and the chain of quartic oscillators. We want to test the result
found previously by us through the finite heat bath canonical ensemble
(cond-mat/0210525), which is an application of Tsallis' statistics. We see that
the results found here are in very good agreement with the theoretical
predicted value. This suggests that this kind of finite systems is ergodic, and
that they do not provide ``bad'' statistics.
