CASIN(3POSIX)

💖 CASIN(3POSIX) — the complex arc sine page, bestie edition 💖

okay so real talk: this is part of the POSIX Programmer's Manual 🫶 and it lives at CASIN(3POSIX). Before we get into it, a lil heads up from the top of the page:

The Linux implementation of this interface may differ (consult the corresponding Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux. 😭

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✨ PROLOG ✨

This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the corresponding Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux. 💀

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🌸 NAME 🌸

casin, casinf, casinl — the complex arc sine functions, three sisters, one vibe 👑

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🎀 SYNOPSIS 🎀

#include <complex.h>

double complex casin(double complex z);
float complex casinf(float complex z);
long double complex casinl(long double complex z);

look at them. so neat. so complex.h. we love to see it 🦋

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💅 DESCRIPTION 💅

The functionality described on this reference page is aligned with the ISO C standard. Any conflict between the requirements described here and the ISO C standard is unintentional — like, we're not trying to start drama with ISO C, fr fr. This volume of POSIX.1‐2017 defers to the ISO C standard. periodt. 💖

These functions shall compute the complex arc sine of z, with branch cuts outside the interval [-1, +1] along the real axis. yes bestie, the branch cuts are OUTSIDE that interval. iykyk 🌈

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⭐ RETURN VALUE ⭐

These functions shall return the complex arc sine value, in the range of a strip mathematically unbounded along the imaginary axis and in the interval [-π/2, +π/2] along the real axis. she's got range (literally) 💜

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💀 ERRORS 💀

No errors are defined. none. zero. the girlies are unbothered 😌✨

The following sections are informative. (translation: they're lore, not law 🧚)

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🌈 EXAMPLES 🌈

None. 🙈 no examples, no notes, nothing. iconic minimalism honestly.

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🍓 APPLICATION USAGE 🍓

None. again! nothing to add. she said "figure it out bestie" 💅

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🦋 RATIONALE 🦋

None. the reasoning is a mystery, and honestly? we respect it 👑

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🌟 FUTURE DIRECTIONS 🌟

None. the future is wide open. no promises made, no promises broken 💖

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🔥 SEE ALSO 🔥

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

go read those next, bestie, they're part of the same cinematic universe 🎬

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👑 COPYRIGHT 👑

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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okay that's the whole page, no cap 💖 huge shoutout to IEEE/The Open Group, 2017 for this absolute classic — mwah, we're obsessed, see you in the next man page bestie 🎀✨💅