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atan

(PHP 4, PHP 5, PHP 7, PHP 8)

atan — 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

num

The argument to process

Return Values

The arc tangent of num in radians.

See Also