# ASIN

Returns the arcsine of a numeric input as an angle in radians.

## Syntax

`ASIN(number)`

### Parameters

#### number

A number between -1 and 1. If the value is `null`, the function returns `null`.

## Examples

Calculates the arcsine of 0.9 and stores the result in a new column named `asin`:

```esql
ROW a=.9
| EVAL asin=ASIN(a)
```
