summaryrefslogtreecommitdiffstats
path: root/man3/casin.3
blob: 17fa10fc8a97ae5acb3a01c429285df285dcc3f4 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
'\" t
.\" Copyright 2002 Walter Harms (walter.harms@informatik.uni-oldenburg.de)
.\"
.\" SPDX-License-Identifier: GPL-1.0-or-later
.\"
.TH casin 3 (date) "Linux man-pages (unreleased)"
.SH NAME
casin, casinf, casinl \- complex arc sine
.SH LIBRARY
Math library
.RI ( libm ", " \-lm )
.SH SYNOPSIS
.nf
.B #include <complex.h>
.PP
.BI "double complex casin(double complex " z );
.BI "float complex casinf(float complex " z );
.BI "long double complex casinl(long double complex " z );
.fi
.SH DESCRIPTION
These functions calculate the complex arc sine of
.IR z .
If \fIy\ =\ casin(z)\fP, then \fIz\ =\ csin(y)\fP.
The real part of
.I y
is chosen in the interval [\-pi/2,pi/2].
.PP
One has:
.PP
.nf
    casin(z) = \-i clog(iz + csqrt(1 \- z * z))
.fi
.SH ATTRIBUTES
For an explanation of the terms used in this section, see
.BR attributes (7).
.ad l
.nh
.TS
allbox;
lbx lb lb
l l l.
Interface	Attribute	Value
T{
.BR casin (),
.BR casinf (),
.BR casinl ()
T}	Thread safety	MT-Safe
.TE
.hy
.ad
.sp 1
.SH STANDARDS
C11, POSIX.1-2008.
.SH HISTORY
glibc 2.1.
C99, POSIX.1-2001.
.SH SEE ALSO
.BR clog (3),
.BR csin (3),
.BR complex (7)