acoshl(3) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | ATTRIBUTES | CONFORMING TO | SEE ALSO | COLOPHON

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

NAME top

       acosh, acoshf, acoshl - inverse hyperbolic cosine function

SYNOPSIS top

       #include <math.h>

       double acosh(double x);
       float acoshf(float x);
       long double acoshl(long double x);

       Link with -lm.

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       acosh():
           _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
               || _XOPEN_SOURCE >= 500
               || /* Since glibc 2.19: */ _DEFAULT_SOURCE
               || /* Glibc versions <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE
       acoshf(), acoshl():
           _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
               || /* Since glibc 2.19: */ _DEFAULT_SOURCE
               || /* Glibc versions <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE

DESCRIPTION top

       These functions calculate the inverse hyperbolic cosine of x; that is
       the value whose hyperbolic cosine is x.

RETURN VALUE top

       On success, these functions return the inverse hyperbolic cosine of
       x.

       If x is a NaN, a NaN is returned.

       If x is +1, +0 is returned.

       If x is positive infinity, positive infinity is returned.

       If x is less than 1, a domain error occurs, and the functions return
       a NaN.

ERRORS top

       See math_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 1
              errno is set to EDOM.  An invalid floating-point exception
              (FE_INVALID) is raised.

ATTRIBUTES top

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

       ┌─────────────────────────────┬───────────────┬─────────┐
       │Interface                    Attribute     Value   │
       ├─────────────────────────────┼───────────────┼─────────┤
       │acosh(), acoshf(), acoshl()  │ Thread safety │ MT-Safe │
       └─────────────────────────────┴───────────────┴─────────┘

CONFORMING TO top

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

       The variant returning double also conforms to SVr4, 4.3BSD.

SEE ALSO top

       asinh(3), atanh(3), cacosh(3), cosh(3), sinh(3), tanh(3)

COLOPHON top

       This page is part of release 5.08 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/.

                                 2017-09-15                         ACOSH(3)