Primal graph (hypergraphs)

In mathematics, a hypergraph is a generalization of a graph in which an edge can join any number of vertices. Formally, a hypergraph ${\displaystyle H}$ is a pair ${\displaystyle H=(X,E)}$ where ${\displaystyle X}$ is a set of elements called nodes or vertices, and ${\displaystyle E}$ is a set of non-empty subsets of ${\displaystyle X}$ called hyperedges or edges. Therefore, ${\displaystyle E}$ is a subset of ${\displaystyle {\mathcal {P}}(X)\setminus \{\emptyset \}}$, where ${\displaystyle {\mathcal {P}}(X)}$ is the power set of ${\displaystyle X}$.

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