CACOSH(3P)

🦋 CACOSH(3P) — POSIX Programmer's Manual 🦋

okay bestie, welcome to the POSIX Programmer's Manual, the one and only 💅 this is the CACOSH(3P) page and we're about to get into some complex arc hyperbolic cosine energy. yes it's giving math. yes it's iconic.

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🌸 PROLOG 🌸

okay so real talk first, and this is important:

this manual page is part of the POSIX Programmer's Manual. the Linux implementation of this interface may differ (so like, go consult the corresponding Linux manual page for the deets on Linux behavior), or — and this is the messy part — the interface may not be implemented on Linux at all. no cap. check before you ship.

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✨ NAME ✨

cacosh, cacoshf, cacoshl — complex arc hyperbolic cosine functions 🫶

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💖 SYNOPSIS 💖

#include <complex.h>

double complex cacosh(double complex z);
float complex cacoshf(float complex z);
long double complex cacoshl(long double complex z);

three functions, three vibes, one job. the f one is float, the l one is long double, and the plain one is double. that's the whole naming scheme, iykyk.

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👑 DESCRIPTION 👑

so, the functionality described on this reference page is aligned with the ISO C standard. and if there's any conflict between what's written here and the ISO C standard? that conflict is unintentional, bestie. this volume of POSIX.1‐2017 defers to the ISO C standard. the ISO C standard is the main character here, we're just supporting cast.

and now the actual tea: these functions shall compute the complex arc hyperbolic cosine of z, with a branch cut at values less than 1 along the real axis. that's the part people trip over, so like. write it down. the branch cut is at values less than 1 along the real axis. periodt.

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🔥 RETURN VALUE 🔥

these functions shall return the complex arc hyperbolic cosine value, in the range of a half-strip of non-negative values along the real axis and in the interval [-iπ, +iπ] along the imaginary axis.

so: real part non-negative, imaginary part chilling somewhere between -iπ and +iπ. the range is the whole personality. 🎀

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💀 ERRORS 💀

No errors are defined. that's it. that's the section. no error conditions, nothing to catch, nothing to handle. we love a low-drama function.

and btw, the following sections are informative (aka, not normative requirements, just vibes and context):

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🙈 EXAMPLES 🙈

None.

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🌈 APPLICATION USAGE 🌈

None.

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🧚 RATIONALE 🧚

None.

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⭐ FUTURE DIRECTIONS ⭐

None.

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💜 SEE ALSO 💜

• ccosh()
• The Base Definitions volume of POSIX.1‐2017, <complex.h>

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🍓 COPYRIGHT 🍓

okay legal moment, don't skip it, it's important:

Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1-2017, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 7, 2018 Edition, Copyright (C) 2018 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group.

In the event of any discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html .

Any typographical or formatting errors that appear in this page are most likely to have been introduced during the conversion of the source files to man page format. To report such errors, see https://www.kernel.org/doc/man-pages/reporting_bugs.html .

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and that's the whole page bestie!! this one came to you from IEEE/The Open Group, dated 2017, and it's the CACOSH(3P) page of the POSIX Programmer's Manual — stay complex, stay hyperbolic, go take your arc cosine and slay 💖✨