- TIBCO BusinessEvents®
- Standard
- Math

# Math.asin()

## Signature

`double asin (double a)`

## Domain

ACTION, CONDITION, QUERY

## Description

Returns the arc sine of an angle, in the range of -pi/2 through pi/2. Special cases:
If the argument is NaN or its absolute value is greater than 1, then the result is NaN.
If the argument is zero, then the result is a zero with the same sign as the argument.
A result must be within 1 ulp of the correctly rounded result. Results must be semi-monotonic.

## Parameters

Name | Type | Description
--- | --- | ---
`a` | `double` | The value whose arc sine is to be returned.

## Returns

Type | Description
--- | ---
`double` | The arc sine of the argument.

## Cautions

none