man3/cabs.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 CABS 3 2021-03-22 GNU "Linux Programmer's Manual"
   6 .SH NAME
   7 cabs, cabsf, cabsl \- absolute value of a complex number
   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 cabs(double complex " z );
  16 .BI "float cabsf(float complex " z );
  17 .BI "long double cabsl(long double complex " z );
  18 .fi
  19 .SH DESCRIPTION
  20 These functions return the absolute value of the complex number
  21 .IR z .
  22 The result is a real number.
  23 .SH VERSIONS
  24 These functions first appeared in glibc in version 2.1.
  25 .SH ATTRIBUTES
  26 For an explanation of the terms used in this section, see
  27 .BR attributes (7).
  28 .ad l
  29 .nh
  30 .TS
  31 allbox;
  32 lbx lb lb
  33 l l l.
  34 Interface       Attribute       Value
  35 T{
  36 .BR cabs (),
  37 .BR cabsf (),
  38 .BR cabsl ()
  39 T}      Thread safety   MT-Safe
  40 .TE
  41 .hy
  42 .ad
  43 .sp 1
  44 .SH CONFORMING TO
  45 C99, POSIX.1-2001, POSIX.1-2008.
  46 .SH NOTES
  47 The function is actually an alias for
  48 .I "hypot(a,\ b)"
  49 (or, equivalently,
  50 .IR "sqrt(a*a\ +\ b*b)" ).
  51 .SH SEE ALSO
  52 .BR abs (3),
  53 .BR cimag (3),
  54 .BR hypot (3),
  55 .BR complex (7)