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():

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

errno is set to EDOM (but see BUGS). An invalid floating-point exception (FE_INVALID) is raised.

Range error: result overflow

An overflow floating-point exception (FE_OVERFLOW) is raised.

ATTRIBUTES¶

Multithreading (see pthreads(7))¶

The tan(), tanf(), and tanl() functions are thread-safe.

CONFORMING TO¶

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

BUGS¶

Before version 2.10, the glibc implementation did not set errno to EDOM when a domain error occurred.

SEE ALSO¶

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

COLOPHON¶

This page is part of release 3.74 of the Linux man-pages project. A description of the project, information about reporting bugs, and the latest version of this page, can be found at http://www.kernel.org/doc/man-pages/.