sincos, sincosf, sincosl - calculate sin and cos simultaneously
#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.
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.
These functions return
void.
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
- An invalid floating-point exception (FE_INVALID) is raised.
These functions do not set
errno.
These functions first appeared in glibc in version 2.1.
For an explanation of the terms used in this section, see
attributes(7).
| Interface |
Attribute |
Value |
| sincos (), sincosf (), sincosl () |
Thread safety |
MT-Safe |
These functions are GNU extensions.
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
cos(3),
sin(3),
tan(3)