TAN(3)							     Linux Programmer's Manual							    TAN(3)

NAME

       tan, tanf, tanl - tangent function

SYNOPSIS

       #include <math.h>

       double tan(double x);
       float tanf(float x);
       long double tanl(long double x);

       Link with -lm.

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       tanf(), tanl(): _BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 600 || _ISOC99_SOURCE; or cc -std=c99

DESCRIPTION

       The tan() function returns the tangent of x, where x is given in radians.

RETURN VALUE

       On success, these functions return the tangent of x.

       If x is a NaN, a NaN is returned.

       If x is positive infinity or negative infinity, a domain error occurs, and a NaN is returned.

       If  the correct result would overflow, a range error occurs, and the functions return HUGE_VAL, HUGE_VALF, or HUGE_VALL, respectively, with
       the mathematically correct sign.

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.

       Range error: result overflow
	      An overflow floating-point exception (FE_OVERFLOW) is raised.

       These functions do not set errno.

CONFORMING TO

       C99, POSIX.1-2001.  The variant returning double also conforms to SVr4, 4.3BSD, C89.

SEE ALSO

       acos(3), asin(3), atan(3), atan2(3), cos(3), ctan(3), sin(3)

COLOPHON

       This page is part of release 3.25 of the Linux man-pages project.  A description of the project, and information about reporting bugs,  can
       be found at http://www.kernel.org/doc/man-pages/.

								    2008-08-05								    TAN(3)