CATANH

Section: Linux Programmer's Manual (3)
Updated: 2015-04-19
Index Return to Main Contents

---

 

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);

Link with -lm.  

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>\n", argv[0]);
        exit(EXIT_FAILURE);
    }

    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(EXIT_SUCCESS); }  

SEE ALSO

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

COLOPHON

This page is part of release 4.13 of the Linux man-pages project. A description of the project, information about reporting bugs, and the latest version of this page, can be found at https://www.kernel.org/doc/man-pages/.

---

 

Index

NAME

SYNOPSIS

DESCRIPTION

VERSIONS

ATTRIBUTES

CONFORMING TO

EXAMPLE

SEE ALSO

COLOPHON