atan
atan
(PHP 4, PHP 5, PHP 7)
atan — Arc tangent
Description
float atan ( float $arg )
Returns the arc tangent of arg
in radians. atan() is the complementary function of tan(), which means that a==tan(atan(a)) for every value of a that is within atan()'s range.
Parameters
-
arg
-
The argument to process
Return Values
The arc tangent of arg
in radians.
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Licensed under the Creative Commons Attribution License v3.0 or later.
https://secure.php.net/manual/en/function.atan.php