tan(3) Library Functions Manual tan(3) tan, tanf, tanl - (libm -lm) #include double tan(double x); float tanf(float x); long double tanl(long double x); glibc ( feature_test_macros(7)): tanf() tanl(): _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L || /* Since glibc 2.19: */ _DEFAULT_SOURCE || /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE x x . x. x (NaN) NaN. x NaN ( ). HUGE_VAL HUGE_VALF HUGE_VALL . math_error(7) . : : x errno EDOM ( BUGS). (FE_INVALID). : (FE_OVERFLOW). attributes(7). +------------+------------------------------------+--------------------+ || | | +------------+------------------------------------+--------------------+ |tan() | | MT-Safe | |tanf() | | | |tanl() | | | +------------+------------------------------------+--------------------+ C11, POSIX.1-2008. C99 POSIX.1-2001. double SVr4 4.3BSD C89. glibc 2.10 glibc errno EDOM . acos(3) asin(3) atan(3) atan2(3) cos(3) ctan(3) sin(3) 3 . . : . 6.18 8 2026 tan(3)