Unit matrix

Set

context $n\in \mathbb N$
context $R$ … ring
definiendum $ (I_n)_{ij} := \begin{cases} e & \mathrm{if}\ i=j\\\\ 0 & \mathrm{else} \end{cases}$
postulate $ I_n \in \mathrm{SquareMatrix}(n,R) $

Discussion

Reference

Wikipedia: Unit matrix

Parents

Element of

Matrix ring