ATANH(3) BSD Library Functions Manual ATANH(3)NAME
atanh, atanhf — inverse hyperbolic tangent functions
LIBRARY
Math Library (libm, -lm)
SYNOPSIS
#include <math.h>
double
atanh(double x);
float
atanhf(float x);
DESCRIPTION
The atanh() and the atanhf() functions compute the inverse hyperbolic
tangent of the real argument x. For a discussion of error due to round‐
off, see math(3).
RETURN VALUES
The atanh() and the atanhf() functions return the inverse hyperbolic tan‐
gent of x if successful. If the argument has absolute value 1, a divide-
by-zero exception is raised and an infinity is returned. If |x| > 1, an
invalid exception is raised and an NaN is returned.
SEE ALSOacosh(3), asinh(3), exp(3), fenv(3), math(3)HISTORY
The atanh() function appeared in 4.3BSD.
BSD January 14, 2005 BSD