CATANH(3) Linux Programmer's 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) - clog(1 - z))

VERSIONS
       These functions first appeared in glibc in version 2.1.

ATTRIBUTES
       For   an   explanation   of   the  terms  used  in  this  section,  see
       attributes(7).

       ┌───────────────────────────────┬───────────────┬─────────┐
       │Interface                      │ Attribute     │ Value   │
       ├───────────────────────────────┼───────────────┼─────────┤
       │catanh(), catanhf(), catanhl() │ Thread safety │ MT-Safe │
       └───────────────────────────────┴───────────────┴─────────┘
CONFORMING TO
       C99.

EXAMPLE
       /* Link with "-lm" */

       #include 
       #include 
       #include 
       #include 

       int
       main(int argc, char *argv[])
       {
           double complex z, c, f;

           if (argc != 3) {
               fprintf(stderr, "Usage: %s  \n", argv[0]);
               exit(EXITFAILURE);
           }

           z = atof(argv[1]) + atof(argv[2]) * I;

           c = catanh(z);
           printf("catanh() = %6.3f %6.3f*i\n", creal(c), cimag(c));

           f = 0.5 * (clog(1 + z) - clog(1 - z));
           printf("formula  = %6.3f %6.3f*i\n", creal(f2), cimag(f2));

           exit(EXITSUCCESS);
       }

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

COLOPHON
       This page is part of release 3.53 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/.



                                  2011-09-15                         CATANH(3)