> For the complete documentation index, see [llms.txt](https://docs.cascade.io/cascade/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.cascade.io/cascade/functions-and-expressions/functions/logical/null.md).

# NULL

NULL(  )

Returns `NaN`

### Arguments

None

### Output

A single instance of`NaN` or a column of `NaN`values

### Example

```
NULL() = NaN
```