# Function trace #

Calculate the trace of a matrix: the sum of the elements on the main diagonal of a square matrix.

## Syntax #

```
math.trace(x)
```

### Parameters #

Parameter | Type | Description |
---|---|---|

`x` |
Array | Matrix | A matrix |

### Returns #

Type | Description |
---|---|

number | The trace of `x` |

## Examples #

```
math.trace([[1, 2], [3, 4]]) // returns 5
const A = [
[1, 2, 3],
[-1, 2, 3],
[2, 0, 3]
]
math.trace(A) // returns 6
```