atanh(3) [redhat man page]

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

NAME

       atanh - inverse hyperbolic tangent function

SYNOPSIS

       #include <math.h>

       double atanh(double x);

DESCRIPTION

       The  atanh()  function  calculates  the	inverse hyperbolic tangent of x; that is the value whose hyperbolic tangent is x.  If the absolute
       value of x is greater than 1.0, acosh() returns not-a-number (NaN) and errno is set.

ERRORS

       EDOM   x is out of range.

CONFORMING TO

       SVID 3, POSIX, BSD 4.3, ISO 9899

SEE ALSO

       asinh(3), acosh(3), cosh(3), sinh(3), tanh(3)

								    1993-06-13								  ATANH(3)

ATANH(3)						   BSD 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 hyperbolic 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 FreeBSD 10.0, respectively.

BSD
								   June 9, 2013 							       BSD