# Graph Theory

I have this rosy view of graph theory being elegant, but I’ve never set aside time to dive deeply into it. One day…

 Random Link ¯\_(ツ)_/¯ Nov 13, 2017 » Modeling Influence with Graphs 3 min; updated Jun 20, 2021 Graphs, $$G = (V, E)$$ $$N \times N$$ Adjacency Matrix $$N \times L$$ Incidence Matrix $$A = \begin{bmatrix}0 & 1 & 0 & 0 \\ 0 & 0 & 1 & 0 \\ 1 & 0 & 0 & 0 \\ 0 & 0 & 0 & 1\end{bmatrix}$$ $$\hat{A} = \begin{bmatrix}1 & 0 & -1 & 0 \\ -1 & 1 & 0 & 0 \\ 0 & -1 & 1 & -1 \\ 0 & 0 & 0 & 1\end{bmatrix}$$ $$V$$ = set of $$N$$ nodes$$E$$ = set of $$L$$ links $$A_{ij} = 1$$ iff $$(i, j) \in E$$Note that $$A$$ need not be symmetric for directed graphs....