xref: /freebsd/lib/msun/man/cospi.3 (revision dce5f3abed7181cc533ca5ed3de44517775e78dd)
1*dce5f3abSSteve Kargl.\" Copyright (c) 2017 Steven G. Kargl <kargl@FreeBSD.org>
2*dce5f3abSSteve Kargl.\" All rights reserved.
3*dce5f3abSSteve Kargl.\"
4*dce5f3abSSteve Kargl.\" Redistribution and use in source and binary forms, with or without
5*dce5f3abSSteve Kargl.\" modification, are permitted provided that the following conditions
6*dce5f3abSSteve Kargl.\" are met:
7*dce5f3abSSteve Kargl.\" 1. Redistributions of source code must retain the above copyright
8*dce5f3abSSteve Kargl.\"    notice, this list of conditions and the following disclaimer.
9*dce5f3abSSteve Kargl.\" 2. Redistributions in binary form must reproduce the above copyright
10*dce5f3abSSteve Kargl.\"    notice, this list of conditions and the following disclaimer in the
11*dce5f3abSSteve Kargl.\"    documentation and/or other materials provided with the distribution.
12*dce5f3abSSteve Kargl.\"
13*dce5f3abSSteve Kargl.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
14*dce5f3abSSteve Kargl.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15*dce5f3abSSteve Kargl.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16*dce5f3abSSteve Kargl.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
17*dce5f3abSSteve Kargl.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18*dce5f3abSSteve Kargl.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19*dce5f3abSSteve Kargl.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20*dce5f3abSSteve Kargl.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21*dce5f3abSSteve Kargl.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22*dce5f3abSSteve Kargl.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23*dce5f3abSSteve Kargl.\" SUCH DAMAGE.
24*dce5f3abSSteve Kargl.\"
25*dce5f3abSSteve Kargl.\" $FreeBSD$
26*dce5f3abSSteve Kargl.\"
27*dce5f3abSSteve Kargl.Dd April 1, 2017
28*dce5f3abSSteve Kargl.Dt COSPI 3
29*dce5f3abSSteve Kargl.Os
30*dce5f3abSSteve Kargl.Sh NAME
31*dce5f3abSSteve Kargl.Nm cospi ,
32*dce5f3abSSteve Kargl.Nm cospif ,
33*dce5f3abSSteve Kargl.Nm cospil
34*dce5f3abSSteve Kargl.Nd half\(encycle cosine functions
35*dce5f3abSSteve Kargl.Sh LIBRARY
36*dce5f3abSSteve Kargl.Lb libm
37*dce5f3abSSteve Kargl.Sh SYNOPSIS
38*dce5f3abSSteve Kargl.In math.h
39*dce5f3abSSteve Kargl.Ft double
40*dce5f3abSSteve Kargl.Fn cospi "double x"
41*dce5f3abSSteve Kargl.Ft float
42*dce5f3abSSteve Kargl.Fn cospif "float x"
43*dce5f3abSSteve Kargl.Ft long double
44*dce5f3abSSteve Kargl.Fn cospil "long double x"
45*dce5f3abSSteve Kargl.Sh DESCRIPTION
46*dce5f3abSSteve KarglThe
47*dce5f3abSSteve Kargl.Fn cospi ,
48*dce5f3abSSteve Kargl.Fn cospif ,
49*dce5f3abSSteve Kargland
50*dce5f3abSSteve Kargl.Fn cospil
51*dce5f3abSSteve Karglfunctions compute the cosine of
52*dce5f3abSSteve Kargl.Fa "\(*p \(mu x" .
53*dce5f3abSSteve Kargland measure angles in half-cycles.
54*dce5f3abSSteve Kargl.Sh RETURN VALUES
55*dce5f3abSSteve KarglThe
56*dce5f3abSSteve Kargl.Fn cospi ,
57*dce5f3abSSteve Kargl.Fn cospif ,
58*dce5f3abSSteve Kargland
59*dce5f3abSSteve Kargl.Fn cospil
60*dce5f3abSSteve Karglfunctions returns
61*dce5f3abSSteve Kargl.Fn cos "\(*p \(mu x" .
62*dce5f3abSSteve KarglIf \*(Bax\*(Ba \*(Ge 2^(p - 1)
63*dce5f3abSSteve Karglwhere p is the floating\(enpoint precision of
64*dce5f3abSSteve Kargl.Ar x ,
65*dce5f3abSSteve Karglthen the returned value is 1 and it has no significance.
66*dce5f3abSSteve Kargl.Sh SPECIAL VALUES
67*dce5f3abSSteve Kargl.Bl -tag
68*dce5f3abSSteve Kargl.It
69*dce5f3abSSteve Kargl.Fn cospi \*(Pm0
70*dce5f3abSSteve Karglreturns 1.
71*dce5f3abSSteve Kargl.It
72*dce5f3abSSteve Kargl.Fn cospi \*(Pmn/2
73*dce5f3abSSteve Karglreturns 0 for positive integers
74*dce5f3abSSteve Kargl.Ar n .
75*dce5f3abSSteve Kargl.It
76*dce5f3abSSteve Kargl.Fn cospi n
77*dce5f3abSSteve Karglreturns 1 for even integers
78*dce5f3abSSteve Kargl.Ar n .
79*dce5f3abSSteve Kargl.It
80*dce5f3abSSteve Kargl.Fn cospi n
81*dce5f3abSSteve Karglreturns \-1 for odd integers
82*dce5f3abSSteve Kargl.Ar n .
83*dce5f3abSSteve Kargl.It
84*dce5f3abSSteve Kargl.Fn cospi \*(Pm\(if
85*dce5f3abSSteve Karglreturn an \*(Na and raises an FE_INVALID exception.
86*dce5f3abSSteve Kargl.It
87*dce5f3abSSteve Kargl.Fn cospi \*(Na
88*dce5f3abSSteve Karglreturn an \*(Na and raises an FE_INVALID exception.
89*dce5f3abSSteve Kargl.El
90*dce5f3abSSteve Kargl.Sh SEE ALSO
91*dce5f3abSSteve Kargl.Xr cos 3 ,
92*dce5f3abSSteve Kargl.Xr fenv 3 ,
93*dce5f3abSSteve Kargl.Xr math 3 ,
94*dce5f3abSSteve Kargl.Xr sin 3 ,
95*dce5f3abSSteve Kargl.Xr sinpi 3 ,
96*dce5f3abSSteve Kargl.Xr tan 3 ,
97*dce5f3abSSteve Kargl.Xr tanpi 3
98*dce5f3abSSteve Kargl.Sh AUTHORS
99*dce5f3abSSteve KarglThe half\(encycle trignometric functions were written by
100*dce5f3abSSteve Kargl.An Steven G. Kargl Aq Mt kargl@FreeBSD.org .
101*dce5f3abSSteve Kargl.Sh STANDARDS
102*dce5f3abSSteve KarglThese functions conform to
103*dce5f3abSSteve KarglIEEE Std 754\(tm\(en2008 ,
104*dce5f3abSSteve Kargl\(dqIEEE Standard for Floating-Point Arithmetic\(dq
105*dce5f3abSSteve Kargland to
106*dce5f3abSSteve KarglISO/IEC TS 18661-4 ,
107*dce5f3abSSteve Kargl\(dqInformation technology \(em Programming languages, their environments,
108*dce5f3abSSteve Kargland system software interfaces \(em Floating\(enpoint extensions for
109*dce5f3abSSteve KarglC\(dq \(em Part 4: Supplementary functions.
110*dce5f3abSSteve Kargl
111*dce5f3abSSteve Kargl
112