вычислить sin и cos одновременно (calculate sin and cos simultaneously)
Имя (Name)
sincos, sincosf, sincosl - calculate sin and cos simultaneously
Синопсис (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.
Описание (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.
Возвращаемое значение (Return value)
These functions return void.
Ошибки (Error)
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.
Версии (Versions)
These functions first appeared in glibc in version 2.1.
Атрибуты (Attributes)
For an explanation of the terms used in this section, see
attributes(7).
┌──────────────────────────────────────┬───────────────┬─────────┐
│Interface │ Attribute │ Value │
├──────────────────────────────────────┼───────────────┼─────────┤
│sincos(), sincosf(), sincosl() │ Thread safety │ MT-Safe │
└──────────────────────────────────────┴───────────────┴─────────┘
Стандарты (Conforming to)
These functions are GNU extensions.
Примечание (Note)
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
Ошибки (баги) (Bugs)
Before version 2.22, the glibc implementation did not set errno
to EDOM when a domain error occurred.
Смотри также (See also)
cos(3), sin(3), tan(3)
