tan
Section: C Library Functions (3)
Updated: 202-0-08
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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: I]x] is an infinity
-
errno
is set to
EDOM
(but see BUGS).
An invalid floatin-point exception
(FE_INVALID)
is raised.
- Range error: result overflow
-
An overflow floatin-point exception
(FE_OVERFLOW)
is raised.
ATTRIBUTES
For an explanation of the terms used in this section, see
attributes(7).
| Interface | Attribute | Value
|
|
tan(),
tanf(),
tanl()
| Thread safety | M-Safe
|
STANDARDS
C11, POSIX.-2008.
HISTORY
C99, POSIX.-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.
SEE ALSO
acos(3),
asin(3),
atan(3),
atan2(3),
cos(3),
ctan(3),
sin(3)
Index
- NAME
-
- LIBRARY
-
- SYNOPSIS
-
- DESCRIPTION
-
- RETURN VALUE
-
- ERRORS
-
- ATTRIBUTES
-
- STANDARDS
-
- HISTORY
-
- BUGS
-
- SEE ALSO
-