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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
            An invalid floating-point exception (FE_INVALID) is raised.

     These functions do not set errno.

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