NAME
atanh, atanhf,
atanhl —
inverse hyperbolic tangent
functions
SYNOPSIS
#include
<math.h>
double
atanh(double
x);
float
atanhf(float
x);
long double
atanhl(long
double x);
DESCRIPTION
The
atanh()
function computes the inverse hyperbolic tangent of the real argument
x. The
atanhf()
function is a single precision version of atanh().
The
atanhl()
function is an extended precision version of
atanh().
RETURN VALUES
If |x|>=1,
atanh(x),
atanhf(x) and
atanhl(x) return +infinity,
-infinity or NaN, and set the global variable errno to
EDOM.
SEE ALSO
HISTORY
The atanh() function appeared in
4.3BSD.