Dependency graph

In mathematics, computer science and digital electronics, a dependency graph is a directed graph representing dependencies of several objects towards each other. It is possible to derive an evaluation order or the absence of an evaluation order that respects the given dependencies from the dependency graph.

Given a set of objects ${\displaystyle S}$ and a transitive relation ${\displaystyle R\subseteq S\times S}$ with ${\displaystyle (a,b)\in R}$ modeling a dependency "a needs b evaluated first", the dependency graph is a graph ${\displaystyle G=(S,T)}$ with ${\displaystyle T\subseteq R}$ and R being the transitive closure of T.

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