CATAN(3POSIX)

🌈 CATAN — the complex arc tangent situation 💅

okay bestie, so this one lives in the POSIX Programmer's Manual, and it's the 3POSIX page for catan, catanf, and catanl. Come sit with me, it's actually not that deep. 🫶

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✨ PROLOG ✨

Real talk first: this manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ — so if you're on Linux, go consult the corresponding Linux manual page for the deets on Linux behavior. Or, plot twist, the interface might just not be implemented on Linux at all. Not me warning you before you even start 😭

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🌸 NAME 🌸

catan, catanf, catanl — the complex arc tangent functions. Three of them. Sisters. A whole trio. 👑

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🎀 SYNOPSIS 🎀

#include <complex.h>

double complex catan(double complex z);
float complex catanf(float complex z);
long double complex catanl(long double complex z);

Look at them, all lined up, so organized, so iconic. ✨

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💖 DESCRIPTION 💖

The functionality described on this reference page is aligned with the ISO C standard. And if there's any conflict between the requirements described here and the ISO C standard? That's unintentional, bestie. This volume of POSIX.1‐2017 defers to the ISO C standard. It's giving "the ISO C standard is the referee and we respect her." 💅

So here's the actual tea: these functions shall compute the complex arc tangent of z, with branch cuts outside the interval [-i, +i] along the imaginary axis. That's the whole vibe. Outside [-i, +i], imaginary axis, branch cuts. Write it down. 🦋

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🔥 RETURN VALUE 🔥

These functions shall return the complex arc tangent value, and it lands in the range of a strip mathematically unbounded along the imaginary axis and in the interval [-π/2, +π/2] along the real axis. So: imaginary axis = no limits, she's free 🌈. Real axis = [-π/2, +π/2], she's contained, she's got boundaries, she's healthy. Periodt.

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💀 ERRORS 💀

No errors are defined. Literally none. This function has never done anything wrong in its life, not once. 🙈

Also, heads up: the following sections are informative. So they're the chill, non-mandatory part of the page. 🌸

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🍓 EXAMPLES 🍓

None. Nothing. Empty. The void. We love a low-effort section 💀✨

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🧚 APPLICATION USAGE 🧚

None. Also nothing! Two for two! 😭

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💜 RATIONALE 💜

None. The reasoning? There is no reasoning. She simply exists. Main character energy, no explanation needed. 👑

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⭐ FUTURE DIRECTIONS ⭐

None. The future is empty. We're living in the present. Slay. 🦋

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🌟 SEE ALSO 🌟

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

iykyk, go read those too, they're the supporting cast. 🫶

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👑 COPYRIGHT 👑

Okay here's the legal part, and I'm keeping every word because bestie, I am not about to get us in trouble:

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 .

ngl, the "referee document" line is doing numbers. The original always wins. Always. 💅

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And that's the whole page, bestie! It came from IEEE/The Open Group, dated 2017, and it's the CATAN(3POSIX) page. Go forth and compute your complex arc tangents responsibly. Mwah. 💖✨🎀