CASINH(3) Library Functions Manual CASINH(3)

casinh casinhf casinhl — complex arc hyperbolic sine functions

#include <complex.h>

double complex casinh(double complex z);
float complex casinhf(float complex z);
long double complex casinhl(long double complex z);

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. This volume of POSIX.1-2024 defers to the ISO C standard.

These functions shall compute the complex arc hyperbolic sine of z, with branch cuts outside the interval [- i, + i] along the imaginary axis.

These functions shall return the complex arc hyperbolic sine value, in the range of a strip mathematically unbounded along the real axis and in the interval [- i ℼ/2, + i ℼ/2] along the imaginary axis.

casinh ( conj ( z)), casinhf ( conjf ( z)), and casinhl ( conjl ( z)) shall return exactly the same value as conj ( casinh ( z)), conjf ( casinhf ( z)), and conjl ( casinhl ( z)), respectively, and casinh ( -z), casinhf ( -z), and casinhl ( -z) shall return exactly the same value as ( z), -casinhf ( z), and z respectively, including for the special values of z below.

If z is +0 + i 0, 0 + i 0 shall be returned.

If z is x + i Inf where x is positive-signed and finite, +Inf + i ℼ/2 shall be returned.

If z is x + i NaN where x is finite, NaN + i NaN shall be returned and the invalid floating-point exception may be raised.

If z is +Inf + iy where y is positive-signed and finite, +Inf + i 0 shall be returned.

If z is +Inf + i Inf, +Inf + i ℼ/4 shall be returned.

If z is +Inf + i NaN, +Inf + i NaN shall be returned.

If z is NaN + i 0, NaN + i 0 shall be returned.

If z is NaN + iy where y is non-zero and finite, NaN + i NaN shall be returned and the invalid floating-point exception may be raised.

If z is NaN + i Inf, ±Inf + i NaN shall be returned; the sign of the real part of the result is unspecified.

If z is NaN + i NaN, NaN + i NaN shall be returned.

No errors are defined.

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csinh(3)

XBD <complex.h>

First released in Issue 6. Derived from the ISO/IEC 9899:1999 (“ISO C99”) standard.

Austin Group Defect 1302 is applied, aligning these functions with the ISO/IEC 9899:2018 standard.

June 14, 2024 posix.fail