tanf(3) Linux Man Page - System Grab Bag

Name

tan, tanf, tanl - tangent function

Library

Math library ( libm ", " -lm )

Synopsis

#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)):

tanf() tanl()

    _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
        || /* Since glibc 2.19: */ _DEFAULT_SOURCE
        || /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE

Description

These functions return 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

For an explanation of the terms used in this section, see attributes(7). allbox; lbx lb lb T{ tan()tanf()tanl()

Interface	Attribute	Value
T}	Thread safety	MT-Safe

Standards

C11, POSIX.1-2008.

History

C99, POSIX.1-2001.

The variant returning double also conforms to SVr4, 4.3BSD, C89.

Bugs

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