Provided by: manpages-dev_6.03-1_all
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.
VERSIONS
These functions were added in glibc 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 │ └───────────────────────────────────────────────────────────────┴───────────────┴─────────┘
STANDARDS
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 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)