  In topological dynamics, one considers a topological space $X$ and a self-map
$f: X \to X$ of $X$ and studies the self-map's properties. In global analysis,
one considers a smooth manifold $M^n$ and a differential equation $\xi: M \to
TM$ on $M$ and studies the flow $\Phi_t: M \times \mathbb{R} \to M$ of the
differential equation. In this paper, we consider a necessary and sufficient
condition for a self-diffeomorphism $f$ of a manifold $M$ to be the time-1 map
$\Phi_1$ of the flow of a differential equation on $M$.
