tan, tanf, tanl - tangent function
#include <math.h> double tan(double x); float tanf(float x); long double tanl(long double x);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
These functions return the tangent of
given in radians.
On success, these functions return the tangent of
x is a NaN, a NaN is returned.
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.
See math_error(7) for information on how to determine whether an error has occurred when calling these functions.
The following errors can occur:
xis an infinity
errno is set to EDOM (but see BUGS). An
invalid floating-point exception (FE_INVALID) is
An overflow floating-point exception (FE_OVERFLOW) is raised.
C99, POSIX.1-2001, POSIX.1-2008.
The variant returning
double also conforms to SVr4, 4.3BSD,
Before version 2.10, the glibc implementation did not set
errno to EDOM when a domain error
This page is part of release 5.10 of the Linux
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