Graph Properties / Features

11. In a directed graph:
    • The in-degree of a vertex in a directed graph, denoted $\text{indeg}(v)$

      $\text{indeg}(v)$

      , is the number of directed edges entering the vertex, and
    • The out-degree of a vertex in a directed graph, denoted $\text{outdeg}(v)$

      $\text{outdeg}(v)$

      , is the number of directed edges leaving the vertex.
    

    In this digraph, we have: $\text{indeg}(1) = 2$ and $\text{outdeg}(1) = 0$; $\text{indeg}(2) = 1$ and $\text{outdeg}(2) = 2$; and $\text{indeg}(3) = 0$ and $\text{outdeg}(3) = 1$. Miriam Briskman, CC BY-NC 4.0.

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