COS
Section: Linux Programmer's Manual (3)
Updated: 20131014
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NAME
cos, cosf, cosl  cosine function
SYNOPSIS
#include <math.h>
double cos(double x);
float cosf(float x);
long double cosl(long double x);
Link with lm.
Feature Test Macro Requirements for glibc (see
feature_test_macros(7)):
cosf(),
cosl():

_BSD_SOURCE  _SVID_SOURCE  _XOPEN_SOURCE >= 600  _ISOC99_SOURCE 
_POSIX_C_SOURCE >= 200112L;
or
cc std=c99
DESCRIPTION
The
cos()
function returns the cosine of
x,
where
x
is
given in radians.
RETURN VALUE
On success, these functions return the cosine 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.
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 floatingpoint exception
(FE_INVALID)
is raised.
ATTRIBUTES
Multithreading (see pthreads(7))
The
cos(),
cosf(),
and
cosl()
functions are threadsafe.
CONFORMING TO
C99, POSIX.12001.
The variant returning
double
also conforms to
SVr4, 4.3BSD.
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),
ccos(3),
sin(3),
sincos(3),
tan(3)
COLOPHON
This page is part of release 3.74 of the Linux
manpages
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/manpages/.
Index
 NAME

 SYNOPSIS

 DESCRIPTION

 RETURN VALUE

 ERRORS

 ATTRIBUTES

 Multithreading (see pthreads(7))

 CONFORMING TO

 BUGS

 SEE ALSO

 COLOPHON
