DragonFly On-Line Manual Pages


ATANH(3)	      DragonFly Library Functions Manual	      ATANH(3)

NAME

atanh, atanhf, atanhl -- inverse hyperbolic tangent functions

LIBRARY

Math Library (libm, -lm)

SYNOPSIS

#include <math.h> double atanh(double x); float atanhf(float x); long double atanhl(long double x);

DESCRIPTION

The atanh(), atanhf(), and atanhl() functions compute the inverse hyper- bolic tangent of the real argument x. For a discussion of error due to roundoff, see math(3).

RETURN VALUES

These functions return the inverse hyperbolic tangent 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 ALSO

acosh(3), asinh(3), exp(3), fenv(3), math(3)

HISTORY

The atanh(), atanhf(), and atanhl() functions appeared in 4.3BSD, FreeBSD 2.0, and DragonFly 3.5, respectively. DragonFly 3.9 June 11, 2013 DragonFly 3.9