ctan(3)

💖 ctan(3) — bestie edition 💖

okay so real talk: this is the Linux man-pages 6.20 page for ctan, ctanf, and ctanl, and it is exactly what it says on the tin — the complex tangent function. gen z approved. math girlies rise 🫶

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✨ NAME ✨

ctan, ctanf, ctanl — the complex tangent function 🌸

📚 LIBRARY 📚

Math library — link it with libm, aka -lm. no -lm, no vibes. periodt 💅

🎀 SYNOPSIS 🎀

#include <complex.h>

double complex ctan(double complex z);
float complex ctanf(float complex z);
long double complex ctanl(long double complex z);

three flavors, one vibe: double, float, long double. pick your precision, bestie 👑

🦋 DESCRIPTION 🦋

okay so these functions literally calculate the complex tangent of z. that's it. that's the whole job. main character energy fr fr.

and the complex tangent function is defined as:

ctan(z) = csin(z) / ccos(z)

like, it's giving "tangent = sine over cosine" but make it ✨complex✨. iykyk 💜

🔥 ATTRIBUTES 🔥

for an explanation of the terms used in this section, go peek at attributes(7).

• ctan(), ctanf(), ctanl() — Thread safety: MT-Safe ✅

so yes bestie, you can call these from multiple threads and it will not be messy. slay.

⭐ STANDARDS ⭐

• C11
• POSIX.1-2008

it's official official. 💅

🌈 HISTORY 🌈

• glibc 2.1 — that's when glibc got in on it
• C99, POSIX.1-2001 — and that's when the standards did

a little throwback moment. iconic 🎀

💀 SEE ALSO 💀

• cabs(3)
• catan(3)
• ccos(3)
• csin(3)
• complex(7)

go read those next, no cap 📖

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and that's the whole page, bestie!! this was Linux man-pages 6.20, dated 2026-02-08, filed under ctan(3). go compute some tangents and be wonderful 💖✨🦋🌸