MATLAB Function Reference |

Lower triangular part of a matrix

**Syntax**

**Description**

```
L = tril(X)
```

returns the lower triangular part of `X`

.

```
L = tril(X,k)
```

returns the elements on and below the kth diagonal of `X`

. `k = 0`

is the main diagonal, `k > 0`

is above the main diagonal, and `k < 0`

is below the main diagonal.

**Examples**

**See Also**

treeplot | trimesh |