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>
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  26 .\"
  27 .\" References consulted:
  28 .\"     Linux libc source code
  29 .\"     Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991)
  30 .\"     386BSD man pages
  31 .\" Modified 1993-07-24 by Rik Faith (faith@cs.unc.edu)
  32 .\" Modified 2002-07-27 by Walter Harms
  33 .\"     (walter.harms@informatik.uni-oldenburg.de)
  34 .TH COS 3 2015-04-19 ""   "Linux Programmer's Manual"
  35 .SH NAME
  36 cos, cosf, cosl \- cosine function
  37 .SH SYNOPSIS
  38 .nf
  39 .B #include <math.h>
  40 .sp
  41 .BI "double cos(double " x );
  42 .br
  43 .BI "float cosf(float " x );
  44 .br
  45 .BI "long double cosl(long double " x );
  46 .fi
  47 .sp
  48 Link with \fI\-lm\fP.
  49 .sp
  50 .in -4n
  51 Feature Test Macro Requirements for glibc (see
  52 .BR feature_test_macros (7)):
  53 .in
  54 .sp
  55 .ad l
  56 .BR cosf (),
  57 .BR cosl ():
  58 .RS 4
  59 _BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE\ >=\ 600 || _ISOC99_SOURCE ||
  60 _POSIX_C_SOURCE\ >=\ 200112L;
  61 .br
  62 or
  63 .I cc\ -std=c99
  64 .RE
  65 .ad
  66 .SH DESCRIPTION
  67 These functions return the cosine of
  68 .IR x ,
  69 where
  70 .I x
  71 is
  72 given in radians.
  73 .SH RETURN VALUE
  74 On success, these functions return the cosine of
  75 .IR x .
  76
  77 If
  78 .I x
  79 is a NaN, a NaN is returned.
  80
  81 If
  82 .I x
  83 is positive infinity or negative infinity,
  84 a domain error occurs,
  85 and a NaN is returned.
  86 .SH ERRORS
  87 See
  88 .BR math_error (7)
  89 for information on how to determine whether an error has occurred
  90 when calling these functions.
  91 .PP
  92 The following errors can occur:
  93 .TP
  94 Domain error: \fIx\fP is an infinity
  95 .I errno
  96 is set to
  97 .BR EDOM
  98 (but see BUGS).
  99 An invalid floating-point exception
 100 .RB ( FE_INVALID )
 101 is raised.
 102 .SH ATTRIBUTES
 103 For an explanation of the terms used in this section, see
 104 .BR attributes (7).
 105 .TS
 106 allbox;
 107 lbw21 lb lb
 108 l l l.
 109 Interface       Attribute       Value
 110 T{
 111 .BR cos (),
 112 .BR cosf (),
 113 .BR cosl ()
 114 T}      Thread safety   MT-Safe
 115 .TE
 116 .SH CONFORMING TO
 117 C99, POSIX.1-2001, POSIX.1-2008.
 118
 119 The variant returning
 120 .I double
 121 also conforms to
 122 SVr4, 4.3BSD.
 123 .SH BUGS
 124 Before version 2.10, the glibc implementation did not set
 125 .\" http://sources.redhat.com/bugzilla/show_bug.cgi?id=6780
 126 .I errno
 127 to
 128 .B EDOM
 129 when a domain error occurred.
 130 .SH SEE ALSO
 131 .BR acos (3),
 132 .BR asin (3),
 133 .BR atan (3),
 134 .BR atan2 (3),
 135 .BR ccos (3),
 136 .BR sin (3),
 137 .BR sincos (3),
 138 .BR tan (3)