sincos(3) Library Functions Manual sincos(3)
NAME
sincos, sincosf, sincosl - calculate sin and cos simultaneously
LIBRARY
Math library (libm, -lm)
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);
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.
ATTRIBUTES
For an explanation of the terms used in this section, see attrib-
utes(7).
┌───────────────────────────────────────────┬───────────────┬─────────┐
│ Interface │ Attribute │ Value │
├───────────────────────────────────────────┼───────────────┼─────────┤
│ sincos(), sincosf(), sincosl() │ Thread safety │ MT-Safe │
└───────────────────────────────────────────┴───────────────┴─────────┘
STANDARDS
GNU.
HISTORY
glibc 2.1.
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 glibc 2.22, the glibc implementation did not set errno to EDOM
when a domain error occurred.
SEE ALSO
cos(3), sin(3), tan(3)
Linux man-pages 6.7 2023-10-31 sincos(3)
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