man3/cos.3

   1 .\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk)
   2 .\" and Copyright 2008, Linux Foundation, written by Michael Kerrisk
   3 .\"     <mtk.manpages@gmail.com>
   4 .\"
   5 .\" SPDX-License-Identifier: Linux-man-pages-copyleft
   6 .\"
   7 .\" References consulted:
   8 .\"     Linux libc source code
   9 .\"     Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991)
  10 .\"     386BSD man pages
  11 .\" Modified 1993-07-24 by Rik Faith (faith@cs.unc.edu)
  12 .\" Modified 2002-07-27 by Walter Harms
  13 .\"     (walter.harms@informatik.uni-oldenburg.de)
  14 .TH COS 3 2021-03-22 "Linux man-pages (unreleased)"
  15 .SH NAME
  16 cos, cosf, cosl \- cosine function
  17 .SH LIBRARY
  18 Math library
  19 .RI ( libm ", " \-lm )
  20 .SH SYNOPSIS
  21 .nf
  22 .B #include <math.h>
  23 .PP
  24 .BI "double cos(double " x );
  25 .BI "float cosf(float " x );
  26 .BI "long double cosl(long double " x );
  27 .fi
  28 .PP
  29 .RS -4
  30 Feature Test Macro Requirements for glibc (see
  31 .BR feature_test_macros (7)):
  32 .RE
  33 .PP
  34 .BR cosf (),
  35 .BR cosl ():
  36 .nf
  37     _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
  38         || /* Since glibc 2.19: */ _DEFAULT_SOURCE
  39         || /* Glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE
  40 .fi
  41 .SH DESCRIPTION
  42 These functions return the cosine of
  43 .IR x ,
  44 where
  45 .I x
  46 is
  47 given in radians.
  48 .SH RETURN VALUE
  49 On success, these functions return the cosine of
  50 .IR x .
  51 .PP
  52 If
  53 .I x
  54 is a NaN, a NaN is returned.
  55 .PP
  56 If
  57 .I x
  58 is positive infinity or negative infinity,
  59 a domain error occurs,
  60 and a NaN is returned.
  61 .SH ERRORS
  62 See
  63 .BR math_error (7)
  64 for information on how to determine whether an error has occurred
  65 when calling these functions.
  66 .PP
  67 The following errors can occur:
  68 .TP
  69 Domain error: \fIx\fP is an infinity
  70 .I errno
  71 is set to
  72 .B EDOM
  73 (but see BUGS).
  74 An invalid floating-point exception
  75 .RB ( FE_INVALID )
  76 is raised.
  77 .SH ATTRIBUTES
  78 For an explanation of the terms used in this section, see
  79 .BR attributes (7).
  80 .ad l
  81 .nh
  82 .TS
  83 allbox;
  84 lbx lb lb
  85 l l l.
  86 Interface       Attribute       Value
  87 T{
  88 .BR cos (),
  89 .BR cosf (),
  90 .BR cosl ()
  91 T}      Thread safety   MT-Safe
  92 .TE
  93 .hy
  94 .ad
  95 .sp 1
  96 .SH STANDARDS
  97 C99, POSIX.1-2001, POSIX.1-2008.
  98 .PP
  99 The variant returning
 100 .I double
 101 also conforms to
 102 SVr4, 4.3BSD.
 103 .SH BUGS
 104 Before version 2.10, the glibc implementation did not set
 105 .\" http://sources.redhat.com/bugzilla/show_bug.cgi?id=6780
 106 .I errno
 107 to
 108 .B EDOM
 109 when a domain error occurred.
 110 .SH SEE ALSO
 111 .BR acos (3),
 112 .BR asin (3),
 113 .BR atan (3),
 114 .BR atan2 (3),
 115 .BR ccos (3),
 116 .BR sin (3),
 117 .BR sincos (3),
 118 .BR tan (3)