TAN

Section: Linux Programmer's Manual (3)
Updated: 2021-03-22
Index Return to Main Contents
 

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(): 

    _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).
InterfaceAttributeValue
tan(), tanf(), tanl() Thread safetyMT-Safe

 

CONFORMING TO

C99, POSIX.1-2001, POSIX.1-2008.

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 5.11 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 https://www.kernel.org/doc/man-pages/.

 

Index

NAME
SYNOPSIS
DESCRIPTION
RETURN VALUE
ERRORS
ATTRIBUTES
CONFORMING TO
BUGS
SEE ALSO
COLOPHON
This document was created by man2html, using the manual pages.
Time: 06:22:46 GMT, May 09, 2021