An $m\times n$ (real or complex) matrix $A$ is a collection of $mn$ entries $(a_{ij})$ which are either real or complex numbers arranged in $m$ rows and $n$ columns as follows: \(\begin{bmatrix}a_{11} & a_{12} & \cdots & a_{1n} \\ a_{21} & a_{22} & \cdots & a_{2n} \\ \vdots&\vdots &\ddots &\vdots \\ a_{m1} & a_{m2} &\cdots & a_{mn}\end{bmatrix}\) Two matrices of the same size may be added together entrywise.
Wikidata ID: Q44337