CATANH(3)		   Linux Programmers Manual		    CATANH(3)



NAME
       catanh, catanhf, catanhl - complex arc tangents hyperbolic

SYNOPSIS
       #include 

       double complex catanh(double complex z);
       float complex catanhf(float complex z);
       long double complex catanhl(long double complex z);

       Link with -lm.

DESCRIPTION
       The  catanh() function calculates the complex arc hyperbolic tangent of
       z.  If y = catanh(z), then z = ctanh(y).  The imaginary part  of  y  is
       chosen in the interval [-pi/2,pi/2].

       One has:

	   catanh(z) = 0.5 * clog((1 + z) / (1 - z))

CONFORMING TO
       C99.

SEE ALSO
       atanh(3), cabs(3), cimag(3), complex(7)

COLOPHON
       This  page  is  part of release 3.05 of the Linux man-pages project.  A
       description of the project, and information about reporting  bugs,  can
       be found at http://www.kernel.org/doc/man-pages/.



				  2007-12-26			     CATANH(3)