# catanh(3) [minix man page]

```CATANH(3)						     Linux Programmer's Manual							 CATANH(3)

NAME
catanh, catanhf, catanhl - complex arc tangents hyperbolic

SYNOPSIS
#include <complex.h>

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

DESCRIPTION
These functions calculate 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, POSIX.1-2001, POSIX.1-2008.

EXAMPLE
/* Link with "-lm" */

#include <complex.h>
#include <stdlib.h>
#include <unistd.h>
#include <stdio.h>

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

if (argc != 3) {
fprintf(stderr, "Usage: %s <real> <imag>
", argv[0]);
exit(EXIT_FAILURE);
}

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

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

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

exit(EXIT_SUCCESS);
}

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

COLOPHON
This page is part of release 4.15 of the Linux man-pages project.  A description of the project, information about reporting bugs, and  the

2015-04-19								 CATANH(3)```

## Check Out this Related Man Page

```CATANH(3)						     Linux Programmer's Manual							 CATANH(3)

NAME
catanh, catanhf, catanhl - complex arc tangents hyperbolic

SYNOPSIS
#include <complex.h>

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

DESCRIPTION
These functions calculate 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, POSIX.1-2001, POSIX.1-2008.

EXAMPLE
/* Link with "-lm" */

#include <complex.h>
#include <stdlib.h>
#include <unistd.h>
#include <stdio.h>

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

if (argc != 3) {
fprintf(stderr, "Usage: %s <real> <imag>
", argv[0]);
exit(EXIT_FAILURE);
}

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

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

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

exit(EXIT_SUCCESS);
}