Definition:Convex Set (Order Theory)

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Definition

Definition 1

A subset $A$ of an ordered set $\left({S, \preceq}\right)$ is convex (in $S$) if and only if:

$\forall x, y \in A: \forall z \in S: x \preceq z \preceq y \implies z \in A$


Definition 2

A subset $A$ of an ordered set $\left({S, \preceq}\right)$ is convex (in $S$) if and only if:

$\forall x, y \in A: \forall z \in S: x \prec z \prec y \implies z \in A$


Also see

  • Results about convex sets can be found here.