===== Incidence matrix =====
==== Set ====
| @#55CCEE: context     | @#55CCEE: $n_v,m_e\in \mathbb N$ | 

| @#FFBB00: definiendum | @#FFBB00: $ M\in \mathrm{it}(n_v,m_e) $ |

| @#55EE55: postulate   | @#55EE55: $ \mathrm{Matrix}(n_v,m_e,\{0,1,2\}) $ |

| @#FFFDDD: for all     | @#FFFDDD: $i\in\mathrm{range}(n_v)$ |

| @#55EE55: postulate   | @#55EE55: $\sum_{j=1}^{m_e} M_{ij}=2 $ |

==== Discussion ====
The index $i$ in $M_{ij}$ labels the vertices and the index $j$ labels the edges. The definition says that every edge has exactly two endpoints.

Every incidence matrix corresponds to (a representative of the isomorphism class of) a [[finite undirected graph]].
==== Parents ====
=== Subset of ===
[[Matrix]]
=== Related ===
[[Finite undirected graph]]