SIN(3) Library Functions Manual SIN(3)

sin sinf sinl — sine function

#include <math.h>

double sin(double x);
float sinf(float x);
long double sinl(long double x);

The functionality described on this reference page is aligned with the ISO C standard. Any conflict between the requirements described here and the ISO C standard is unintentional. This volume of POSIX.1-2008 defers to the ISO C standard.

These functions shall compute the sine of their argument x, measured in radians.

An application wishing to check for error situations should set errno to zero and call (FE_ALL_EXCEPT) before calling these functions. On return, if errno is non-zero or (FE_INVALID | FE_DIVBYZERO | FE_OVERFLOW | FE_UNDERFLOW) is non-zero, an error has occurred.

Upon successful completion, these functions shall return the sine of x.

If x is NaN, a NaN shall be returned.

If x is ±0, x shall be returned.

If x is subnormal, a range error may occur and x should be returned.

If x is ±Inf, a domain error shall occur, and either a NaN (if supported), or an implementation-defined value shall be returned.

These functions shall fail if:

[MX] The x argument is ±Inf.

If the integer expression ( math_errhandling & MATH_ERRNO) is non-zero, then errno shall be set to [EDOM]. If the integer expression ( math_errhandling & MATH_ERREXCEPT) is non-zero, then the invalid floating-point exception shall be raised.

These functions may fail if:

[MX] The value of x is subnormal

If the integer expression ( math_errhandling & MATH_ERRNO) is non-zero, then errno shall be set to [ERANGE]. If the integer expression ( math_errhandling & MATH_ERREXCEPT) is non-zero, then the underflow floating-point exception shall be raised.

#include <math.h>
...
double radians = 45.0 * M_PI / 180;
double result;
...
result = sin(radians);

These functions may lose accuracy when their argument is near a multiple of or is far from 0.0.

On error, the expressions ( math_errhandling & MATH_ERRNO) and ( math_errhandling & MATH_ERREXCEPT) are independent of each other, but at least one of them must be non-zero.

None.

None.

asin(3) , feclearexcept(3) , fetestexcept(3) , isnan(3)

XBD V1_chap04(7) , <math.h>

First released in Issue 1. Derived from Issue 1 of the SVID.

The last two paragraphs of the DESCRIPTION were included as APPLICATION USAGE notes in previous issues.

The () and () functions are added for alignment with the ISO/IEC 9899:1999 (“ISO C99”) standard.

The DESCRIPTION, RETURN VALUE, ERRORS, and APPLICATION USAGE sections are revised to align with the ISO/IEC 9899:1999 (“ISO C99”) standard.

IEC 60559:1989 standard floating-point extensions over the ISO/IEC 9899:1999 (“ISO C99”) standard are marked.

January 1, 2008 posix.fail