man3/casin.3

   1 .\" Copyright 2002 Walter Harms (walter.harms@informatik.uni-oldenburg.de)
   2 .\"
   3 .\" SPDX-License-Identifier: GPL-1.0-or-later
   4 .\"
   5 .TH CASIN 3 2021-03-22 GNU "Linux Programmer's Manual"
   6 .SH NAME
   7 casin, casinf, casinl \- complex arc sine
   8 .SH LIBRARY
   9 Math library
  10 .RI ( libm ", " \-lm )
  11 .SH SYNOPSIS
  12 .nf
  13 .B #include <complex.h>
  14 .PP
  15 .BI "double complex casin(double complex " z );
  16 .BI "float complex casinf(float complex " z );
  17 .BI "long double complex casinl(long double complex " z );
  18 .fi
  19 .SH DESCRIPTION
  20 These functions calculate the complex arc sine of
  21 .IR z .
  22 If \fIy\ =\ casin(z)\fP, then \fIz\ =\ csin(y)\fP.
  23 The real part of
  24 .I y
  25 is chosen in the interval [\-pi/2,pi/2].
  26 .PP
  27 One has:
  28 .PP
  29 .nf
  30     casin(z) = \-i clog(iz + csqrt(1 \- z * z))
  31 .fi
  32 .SH VERSIONS
  33 These functions first appeared in glibc in version 2.1.
  34 .SH ATTRIBUTES
  35 For an explanation of the terms used in this section, see
  36 .BR attributes (7).
  37 .ad l
  38 .nh
  39 .TS
  40 allbox;
  41 lbx lb lb
  42 l l l.
  43 Interface       Attribute       Value
  44 T{
  45 .BR casin (),
  46 .BR casinf (),
  47 .BR casinl ()
  48 T}      Thread safety   MT-Safe
  49 .TE
  50 .hy
  51 .ad
  52 .sp 1
  53 .SH CONFORMING TO
  54 C99, POSIX.1-2001, POSIX.1-2008.
  55 .SH SEE ALSO
  56 .BR clog (3),
  57 .BR csin (3),
  58 .BR complex (7)