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. 2025 Dec 22;28(1):12. doi: 10.3390/e28010012
Algorithm 2 Centroid space-time discretization algoriithm—lattice:
The field is u(r, t) with local dynamics tu=F[u], discretize space over nodes i = 1, …, M and time tk = t0 + kh.
  1. Input: {ui0}, operator Fh includes local and neighboring nodes, step h, and number of steps N.

  2. For each time layer k → k + 1 and each node I, we have the following [58,59]:

(a) Euler/RK: uik+1=uik+hFh(ui1k,uik,ui+1k);
(b) Centroid (implicit) version.
We solve the following equation:
                uik+1=uik+Fh(ui1k+ui1k+12,uik+uik+12,ui+1k+ui+1k+12)
by applying iterations until convergence ui(n+1),k+1ui(n),k+1 tol;
  • 3.

    Output: {uik}, for k=1N.

Discrete cyclic vertices and lattice step are obtained with a continuous model and the vertex map. The flow ϕt:R3R3 generated by the Lorenz system has the following form:        
x˙=σ(yx),  y˙=(ρz),  z˙=xyβz, (21)
with classical parameters σ>0, ρ>0, β>0.
Let X(t; X0)=(x(t), y(t), z(t)) be a solution with initial condition X0.