atan
PHP function
Edit on GitHub ✎
(PHP 4, PHP 5, PHP 7, PHP 8)
Arc tangent
Description
atan(float $num): float
Returns the arc tangent of num in radians. atan() is the inverse function of tan(), which means that $num == tan(atan($num)) for every value of num that is in the domain of atan().
Parameters
numThe argument to process
Return Values
The arc tangent of num in radians.