#### Definition

- A matrix is a rectangular group of numbers (or symbols) with a given number of rows and columns.

#### Example

- The following matrix has two rows and three columns, and is described as a "two by three" (2x3) matrix.

#### LaTeX

```
\begin{bmatrix}
3 & 6 & 2 \\
5 & 1 & 10
\end{bmatrix}
```

#### Notation

- There are a few different ways to represent a matrix. The easiest is with an bold uppercase letter:
**A**

#### code (Python)

```
A = [[3, 6, 2], [5, 1, 10]]
print(A)
```

#### Notes

- The plural of matrix is matrices.
- The size of a matrix is called its dimension or order. It is written with as rows x columns. A matrix with 2 rows and 3 columns is written as 2x3.
- Two matrices are considered equal if and only if:
- They have the same number of rows.
- They have the same number of columns.
- Each corresponding element is equal. i.e. x1
_{11} = x2_{11}

- The 'numpy.matrix' is depreciated, in favour of regular arrays.