CSIN(3) Library Functions Manual CSIN(3)

csin csinf csinl — complex sine functions

#include <complex.h>

double complex csin(double complex z);
float complex csinf(float complex z);
long double complex csinl(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 sine of z.

These functions shall return the complex sine value.

csin ( conj ( iz)), csinf ( conjf ( iz)), and csinl ( conjl ( iz)) shall return exactly the same value as conj ( csin ( iz)), conjf ( csinf ( iz)), and conjl ( csinl ( iz)), respectively, and csin ( -iz), csinf ( -iz), and csinl ( -iz) shall return exactly the same value as ( iz), -csinf ( iz), and -csinl ( iz), respectively, including for the special values of iz below.

If iz is +0 + i 0, -i (+0 + i 0) shall be returned.

If iz is +0 + i Inf, -i (±0 + i NaN) shall be returned and the invalid floating-point exception shall be raised; the sign of the imaginary part of the result is unspecified.

If iz is +0 + i NaN, -i (±0 + i NaN) shall be returned; the sign of the imaginary part of the result is unspecified.

If iz is x + i Inf where x is positive and finite, -i (NaN + i NaN) shall be returned and the invalid floating-point exception shall be raised.

If iz is x + i NaN where x is non-zero and finite, -i (NaN + i NaN) shall be returned and the invalid floating-point exception may be raised.

If iz is +Inf + i 0, -i (+Inf + i 0) shall be returned.

If iz is +Inf + iy where y is positive and finite, -i Inf ( ( y) + ( y)) shall be returned.

If iz is +Inf + i Inf, -i (±Inf + i NaN) shall be returned and the invalid floating-point exception shall be raised; the sign of the imaginary part of the result is unspecified.

If iz is +Inf + i NaN, -i (±Inf + i NaN) shall be returned; the sign of the imaginary part of the result is unspecified.

If iz is NaN + i 0, -i (NaN + i 0) shall be returned.

If iz is NaN + iy where y is any non-zero number, -i (NaN + i NaN) shall be returned and the invalid floating-point exception may be raised.

If iz is NaN + i NaN, -i (NaN + i NaN) shall be returned.

No errors are defined.

None.

None.

The MXC special cases for csin () are derived from those for csinh(3) by applying the formula csin ( z) = ( iz).

None.

casin(3), 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