ATANH(3)                  OpenBSD Programmer's Manual                 ATANH(3)

NAME
     atanh, atanhf - inverse hyperbolic tangent functions

SYNOPSIS
     #include <math.h>

     double
     atanh(double x);

     float
     atanhf(float 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().

RETURN VALUES
     If |x|>=1, atanh(x) and atanhf(x) return +inf, -inf or NaN, and set the
     global variable errno to EDOM.

SEE ALSO
     acosh(3), asinh(3), exp(3), infnan(3), math(3)

HISTORY
     The atanh() function appeared in 4.3BSD.

OpenBSD 3.5                       May 6, 1991                                1
