Movatterモバイル変換

acosh(3) — Linux manual page

NAME \|LIBRARY \|SYNOPSIS \|DESCRIPTION \|RETURN VALUE \|ERRORS \|ATTRIBUTES \|STANDARDS \|HISTORY \|SEE ALSO \|COLOPHON

acosh(3)                 Library Functions Manualacosh(3)

NAME top

       acosh, acoshf, acoshl - inverse hyperbolic cosine function

LIBRARY top

       Math library (libm,-lm)

SYNOPSIS top

#include <math.h>double acosh(doublex);float acoshf(floatx);long double acoshl(long doublex);   Feature Test Macro Requirements for glibc (seefeature_test_macros(7)):acosh():           _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L               || _XOPEN_SOURCE >= 500               || /* Since glibc 2.19: */ _DEFAULT_SOURCE               || /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCEacoshf(),acoshl():           _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L               || /* Since glibc 2.19: */ _DEFAULT_SOURCE               || /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE

DESCRIPTION top

       These functions calculate the inverse hyperbolic cosine ofx; that       is the value whose hyperbolic cosine isx.

RETURN VALUE top

       On success, these functions return the inverse hyperbolic cosine       ofx.       Ifx is a NaN, a NaN is returned.       Ifx is +1, +0 is returned.       Ifx is positive infinity, positive infinity is returned.       Ifx is less than 1, a domain error occurs, and the functions       return a NaN.

ERRORS top

       Seemath_error(7) for information on how to determine whether an       error has occurred when calling these functions.       The following errors can occur:       Domain error:x is less than 1errno is set toEDOM.  An invalid floating-point exception              (FE_INVALID) is raised.

ATTRIBUTES top

       For an explanation of the terms used in this section, seeattributes(7).       ┌──────────────────────────────────────┬───────────────┬─────────┐       │Interface│Attribute│Value│       ├──────────────────────────────────────┼───────────────┼─────────┤       │acosh(),acoshf(),acoshl()          │ Thread safety │ MT-Safe │       └──────────────────────────────────────┴───────────────┴─────────┘

STANDARDS top

       C11, POSIX.1-2008.

HISTORY top

       C99, POSIX.1-2001.       The variant returningdouble also conforms to SVr4, 4.3BSD.

COLOPHON top

       This page is part of theman-pages (Linux kernel and C library       user-space interface documentation) project.  Information about       the project can be found at        ⟨https://www.kernel.org/doc/man-pages/⟩.  If you have a bug report       for this manual page, see       ⟨https://git.kernel.org/pub/scm/docs/man-pages/man-pages.git/tree/CONTRIBUTING⟩.       This page was obtained from the tarball man-pages-6.15.tar.gz       fetched from       ⟨https://mirrors.edge.kernel.org/pub/linux/docs/man-pages/⟩ on       2025-08-11.  If you discover any rendering problems in this HTML       version of the page, or you believe there is a better or more up-       to-date source for the page, or you have corrections or       improvements to the information in this COLOPHON (which isnot       part of the original manual page), send a mail to       man-pages@man7.orgLinux man-pages 6.15            2025-05-17acosh(3)

Pages that refer to this page:asinh(3), atanh(3), cacosh(3), cosh(3), sinh(3), tanh(3)

HTML rendering created 2025-09-06 byMichael Kerrisk, author ofThe Linux Programming Interface.

For details of in-depthLinux/UNIX system programming training courses that I teach, lookhere.

Hosting byjambit GmbH.