> ## Documentation Index
> Fetch the complete documentation index at: https://www.integrate.io/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# ETL: ATAN

> Compute the arc tangent (inverse tangent) of a numeric value in radians. Use ATAN for trigonometric calculations in ETL data transformations.

## Description

Returns the arc tangent of a number.

## Syntax

`ATAN(numeric_expression)`

## Examples

`ATAN(1)` returns π/4.

## Return value datatype

Double

## Impact of null value

If input is null, returns null.

## Description

Returns the arc tangent of a number.

## Syntax

`ATAN(numeric_expression)`

## Examples

`ATAN(1)` returns π/4.

## Return value datatype

Double

## Impact of null value

If input is null, returns null.