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);
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
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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/.
2015-04-19 CATANH(3)