# Definition:Periodic Function/Periodic Element

(Redirected from Definition:Periodic Element)
Let $f: X \to X$ be a function, where $X$ is either $\R$ or $\C$.
Let $L \in X_{\ne 0}$.
Then $L$ is a periodic element of $f$ if and only if:
$\forall x \in X: \map f x = \map f {x + L}$