CASIN(3P)

✨ PROLOG ✨

okay bestie, real talk before we dive in 💖 this page is part of the POSIX Programmer's Manual. the Linux implementation of this interface may differ (so like, go check the corresponding Linux manual page for the deets on Linux behavior), or honestly the interface might not even be implemented on Linux at all. 🙈 no cap.

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🎀 NAME 🎀

casin, casinf, casinl — complex arc sine functions 🦋

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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);

like look at her. three whole flavors. iconic. ✨

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🌸 DESCRIPTION 🌸

so the functionality described on this reference page is aligned with the ISO C standard. if there's any conflict between the requirements described here and the ISO C standard, that's unintentional — nobody's trying to start drama. 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, the branch cuts are outside that interval. write it down. 🖊️

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⭐ RETURN VALUE ⭐

these functions shall return the complex arc sine value, in the range of a strip that's mathematically unbounded along the imaginary axis and in the interval [-π/2, +π/2] along the real axis. so the imaginary part can go absolutely feral (technically) but the real part knows its limits. main character with boundaries. 👑

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🔥 ERRORS 🔥

No errors are defined. not a single one. she simply does not have a problem era. 💅

the following sections are informative — meaning they're the vibes, not the rules.

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🍓 EXAMPLES 🍓

None. we have no examples. we're just that confident. 🫶

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🧚 APPLICATION USAGE 🧚

None. nothing to add bestie, she speaks for herself.

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🌈 RATIONALE 🌈

None. no explanation needed. iykyk.

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🔮 FUTURE DIRECTIONS 🔮

None. the future is unwritten and honestly she's not stressing about it. ✨

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👑 SEE ALSO 👑

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

go read those too, they're part of the lore. 📚

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💖 COPYRIGHT 💖

okay this part is the legal bit so we're being serious for like 30 seconds, stay with me:

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. like, it's the final boss. 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 icon of a manpage came to you from IEEE/The Open Group, 2017, and its header is CASIN(3P) — go forth and compute complex arc sines responsibly. mwah. 💅🎀🌸