# ATAN

ATAN returns the angle, in radians, whose tangent is x. The result is between -pi/2 and +pi/2.

This function is valid in both rules and TurboIntegrator processes.

## Syntax

`ATAN(x)`

Argument |
Description |
---|---|

x |
The tangent of the angle you want to find. |

## Example

ATAN(1) returns .7854.