NAME | SYNOPSIS | DESCRIPTION | VERSIONS | ATTRIBUTES | CONFORMING TO | EXAMPLE | SEE ALSO | COLOPHON

CACOSH(3)                 Linux Programmer's Manual                CACOSH(3)

NAME         top

       cacosh, cacoshf, cacoshl - complex arc hyperbolic cosine

SYNOPSIS         top

       #include <complex.h>
       double complex cacosh(double complex z);
       float complex cacoshf(float complex z);
       long double complex cacoshl(long double complex z);
       Link with -lm.

DESCRIPTION         top

       These functions calculate the complex arc hyperbolic cosine of z.  If
       y = cacosh(z), then z = ccosh(y).  The imaginary part of y is chosen
       in the interval [-pi,pi].  The real part of y is chosen nonnegative.
       One has:
           cacosh(z) = 2 * clog(csqrt((z + 1) / 2) + csqrt((z - 1) / 2))

VERSIONS         top

       These functions first appeared in glibc in version 2.1.

ATTRIBUTES         top

       For an explanation of the terms used in this section, see
       attributes(7).
       ┌───────────────────────────────┬───────────────┬─────────┐
       │Interface                      Attribute     Value   │
       ├───────────────────────────────┼───────────────┼─────────┤
       │cacosh(), cacoshf(), cacoshl() │ Thread safety │ MT-Safe │
       └───────────────────────────────┴───────────────┴─────────┘

CONFORMING TO         top

       C99, POSIX.1-2001, POSIX.1-2008.

EXAMPLE         top

       /* 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 = cacosh(z);
           printf("cacosh() = %6.3f %6.3f*i\n", creal(c), cimag(c));
           f = 2 * clog(csqrt((z + 1)/2) + csqrt((z - 1)/2));
           printf("formula  = %6.3f %6.3f*i\n", creal(f2), cimag(f2));
           exit(EXIT_SUCCESS);
       }

SEE ALSO         top

       acosh(3), cabs(3), ccosh(3), cimag(3), complex(7)

COLOPHON         top

       This page is part of release 4.12 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/.
                                 2015-04-19                        CACOSH(3)

Pages that refer to this page: acosh(3)ccosh(3)complex(7)