xref: /openbsd-src/lib/libm/man/acos.3 (revision 4bc2832d0a071121eb4e4834063fc282081657a1)
1*4bc2832dSnaddy.\"	$OpenBSD: acos.3,v 1.17 2022/03/29 18:15:52 naddy Exp $
2df930be7Sderaadt.\" Copyright (c) 1991 The Regents of the University of California.
3df930be7Sderaadt.\" All rights reserved.
4df930be7Sderaadt.\"
5df930be7Sderaadt.\" Redistribution and use in source and binary forms, with or without
6df930be7Sderaadt.\" modification, are permitted provided that the following conditions
7df930be7Sderaadt.\" are met:
8df930be7Sderaadt.\" 1. Redistributions of source code must retain the above copyright
9df930be7Sderaadt.\"    notice, this list of conditions and the following disclaimer.
10df930be7Sderaadt.\" 2. Redistributions in binary form must reproduce the above copyright
11df930be7Sderaadt.\"    notice, this list of conditions and the following disclaimer in the
12df930be7Sderaadt.\"    documentation and/or other materials provided with the distribution.
136580fee3Smillert.\" 3. Neither the name of the University nor the names of its contributors
14df930be7Sderaadt.\"    may be used to endorse or promote products derived from this software
15df930be7Sderaadt.\"    without specific prior written permission.
16df930be7Sderaadt.\"
17df930be7Sderaadt.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18df930be7Sderaadt.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19df930be7Sderaadt.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20df930be7Sderaadt.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21df930be7Sderaadt.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22df930be7Sderaadt.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23df930be7Sderaadt.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24df930be7Sderaadt.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25df930be7Sderaadt.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26df930be7Sderaadt.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27df930be7Sderaadt.\" SUCH DAMAGE.
28df930be7Sderaadt.\"
29df930be7Sderaadt.\"     from: @(#)acos.3	5.1 (Berkeley) 5/2/91
30df930be7Sderaadt.\"
31*4bc2832dSnaddy.Dd $Mdocdate: March 29 2022 $
32df930be7Sderaadt.Dt ACOS 3
33df930be7Sderaadt.Os
34df930be7Sderaadt.Sh NAME
358a2f5500Sderaadt.Nm acos ,
36854ac34eSmartynas.Nm acosf ,
37854ac34eSmartynas.Nm acosl
388a2f5500Sderaadt.Nd arc cosine functions
39df930be7Sderaadt.Sh SYNOPSIS
4086f9d4cdStedu.In math.h
41df930be7Sderaadt.Ft double
42df930be7Sderaadt.Fn acos "double x"
43df930be7Sderaadt.Ft float
44df930be7Sderaadt.Fn acosf "float x"
45854ac34eSmartynas.Ft long double
46854ac34eSmartynas.Fn acosl "long double x"
47df930be7Sderaadt.Sh DESCRIPTION
48df930be7SderaadtThe
49df930be7Sderaadt.Fn acos
50dfec5a15Sjasonfunction computes the principal value of the arc cosine of
51df930be7Sderaadt.Fa x
52df930be7Sderaadtin the range
539f1be2b6Stb.Bq 0 , pi .
54dfec5a15SjasonThe
55dfec5a15Sjason.Fn acosf
56*4bc2832dSnaddyfunction is a single precision version of
57dfec5a15Sjason.Fn acos .
58854ac34eSmartynasThe
59854ac34eSmartynas.Fn acosl
60*4bc2832dSnaddyfunction is an extended precision version of
61854ac34eSmartynas.Fn acos .
62df930be7Sderaadt.Sh RETURN VALUES
63f0525d41StholoIf |x|>1,
64854ac34eSmartynas.Fn acos "x" ,
65f0525d41Stholo.Fn acosf "x"
66854ac34eSmartynasand
67854ac34eSmartynas.Fn acosl "x"
6843527048Sjasonset the global variable
69f0525d41Stholo.Va errno
701c7c1e02Sschwarzeto
711c7c1e02Sschwarze.Er EDOM .
72df930be7Sderaadt.Sh SEE ALSO
73df930be7Sderaadt.Xr asin 3 ,
74df930be7Sderaadt.Xr atan 3 ,
75df930be7Sderaadt.Xr atan2 3 ,
76350bb3b8Salex.Xr cos 3 ,
77df930be7Sderaadt.Xr cosh 3 ,
78350bb3b8Salex.Xr sin 3 ,
79350bb3b8Salex.Xr sinh 3 ,
80350bb3b8Salex.Xr tan 3 ,
81350bb3b8Salex.Xr tanh 3
82