atanh
(PHP 4 >= 4.1.0)
atanh -- Inverse hyperbolic tangent
Description
float
atanh ( float arg)
Returns the inverse hyperbolic tangent of
arg, i.e. the value whose
hyperbolic tangent is arg.
Nota: Esta función no está implementada en plataformas Windows.
See also atan(), asinh()
and acosh().