# math/atan Arc tangent; returns an angle in radians. ## Syntax

[math/atan $x]

## Parameters - `$x` — Any number ## Examples

[math/atan 0]    # 0
[math/atan 1]    # 0.7853981633974483 (π/4)

## Returns Number — angle in radians, in the range [-π/2, π/2]. ## See Also `math/atan2`, `math/asin`, `math/acos`, `math/tan`