💾 Archived View for gmi.noulin.net › man › man3 › sincos.3.gmi captured on 2022-06-12 at 07:28:19. Gemini links have been rewritten to link to archived content
-=-=-=-=-=-=-
SINCOS(3) Linux Programmer's Manual SINCOS(3)
NAME
sincos, sincosf, sincosl - calculate sin and cos simultaneously
SYNOPSIS
#define _GNU_SOURCE /* See feature_test_macros(7) */
#include <math.h>
void sincos(double x, double *sin, double *cos);
void sincosf(float x, float *sin, float *cos);
void sincosl(long double x, long double *sin, long double *cos);
Link with -lm.
DESCRIPTION
Several applications need sine and cosine of the same angle x. These functions compute both at the same time, and store the results in *sin and *cos. Using
this function can be more efficient than two separate calls to sin(3) and cos(3).
If x is a NaN, a NaN is returned in *sin and *cos.
If x is positive infinity or negative infinity, a domain error occurs, and a NaN is returned in *sin and *cos.
RETURN VALUE
These functions return void.
ERRORS
See math_error(7) for information on how to determine whether an error has occurred when calling these functions.
The following errors can occur:
Domain error: x is an infinity
errno is set to EDOM (but see BUGS). An invalid floating-point exception (FE_INVALID) is raised.
VERSIONS
These functions first appeared in glibc in version 2.1.
ATTRIBUTES
For an explanation of the terms used in this section, see attributes(7).
┌──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┬───────────────┬─────────┐
│Interface │ Attribute │ Value │
├──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┼───────────────┼─────────┤
│sincos(), sincosf(), sincosl() │ Thread safety │ MT-Safe │
└──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┴───────────────┴─────────┘
CONFORMING TO
These functions are GNU extensions.
NOTES
To see the performance advantage of sincos(), it may be necessary to disable gcc(1) built-in optimizations, using flags such as:
cc -O -lm -fno-builtin prog.c
BUGS
Before version 2.22, the glibc implementation did not set errno to EDOM when a domain error occurred.
SEE ALSO
cos(3), sin(3), tan(3)
GNU 2021-03-22 SINCOS(3)