Php/docs/function.atan
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atan
(PHP 4, PHP 5, PHP 7)
atan — Arc tangent
Description
atan
( float $arg
) : float
Returns the arc tangent of arg in radians.
atan() is the inverse 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.
