We chose N x = 2 7 , L = 2π, D = 2 × 10 −1 and δt = 10 −3 for our simulations. The initial **data** is taken to be
u 0 (x) = 10 −1 2 L cos 2πx L .(124)
Without any surprise, the integration reveals striking differences in term of patterns exhibited by the field u(t, x) compared to those obtained from the nonlinear example of Section VIII A; compare panel (b) with panel (a) in Fig. 7.