catanh(3) - BetterMan

catanh(3)

complex arc tangents hyperbolic

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Synopsis

#include <complex.h>
double complex catanh(double complex 
z
);
float complex catanhf(float complex 
z
);
long double complex catanhl(long double complex 
z
);

—

NAME

catanh, catanhf, catanhl - complex arc tangents hyperbolic

LIBRARY

Math library (libm, -lm)

SYNOPSIS

bash

#include <complex.h>

bash

double complex catanh(double complex \nz\n);\n
\nfloat complex catanhf(float complex \nz\n);\n
\nlong double complex catanhl(long double complex \nz\n);

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:

bash

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

ATTRIBUTES

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

Interface	Attribute	Value
catanh (), catanhf (), catanhl ()	Thread safety	MT-Safe

STANDARDS

C11, POSIX.1-2008.

HISTORY

glibc 2.1. C99, POSIX.1-2001.

EXAMPLES

bash

/* Link with "-lm" */
#include <complex.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
int
main(int argc, char *argv[])
{
\n
    double complex z, c, f;
\n
    if (argc != 3) {
\n
        fprintf(stderr, "Usage: %s <real> <imag>\n", argv[0]);
\n
        exit(EXIT_FAILURE);
\n
    }
\n
    z = atof(argv[1]) + atof(argv[2]) * I;
\n
    c = catanh(z);
\n
    printf("catanh() = %6.3f %6.3f*i\n", creal(c), cimag(c));
\n
    f = 0.5 * (clog(1 + z) - clog(1 - z));
\n
    printf("formula  = %6.3f %6.3f*i\n", creal(f), cimag(f));
\n
    exit(EXIT_SUCCESS);
}