man3/cbrt.3

   1 .\" Copyright 1995 Jim Van Zandt <jrv@vanzandt.mv.com>
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  24 .\"
  25 .\" changed `square root' into `cube root' - aeb, 950919
  26 .\"
  27 .\" Modified 2002-07-27 Walter Harms
  28 .\" (walter.harms@informatik.uni-oldenburg.de)
  29 .\"
  30 .TH CBRT 3  2017-09-15 "GNU"  "Linux Programmer's Manual"
  31 .SH NAME
  32 cbrt, cbrtf, cbrtl \- cube root function
  33 .SH SYNOPSIS
  34 .nf
  35 .B #include <math.h>
  36 .PP
  37 .BI "double cbrt(double " x );
  38 .BI "float cbrtf(float " x );
  39 .BI "long double cbrtl(long double " x );
  40 .fi
  41 .PP
  42 Link with \fI\-lm\fP.
  43 .PP
  44 .in -4n
  45 Feature Test Macro Requirements for glibc (see
  46 .BR feature_test_macros (7)):
  47 .in
  48 .PP
  49 .ad l
  50 .BR cbrt ():
  51 .br
  52 .RS 4
  53 _ISOC99_SOURCE || _POSIX_C_SOURCE\ >=\ 200112L
  54     || _XOPEN_SOURCE\ >=\ 500
  55 .\"    || _XOPEN_SOURCE\ &&\ _XOPEN_SOURCE_EXTENDED
  56     || /* Since glibc 2.19: */ _DEFAULT_SOURCE
  57     || /* Glibc versions <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE
  58 .RE
  59 .BR cbrtf (),
  60 .BR cbrtl ():
  61 .RS 4
  62 _ISOC99_SOURCE || _POSIX_C_SOURCE\ >=\ 200112L
  63     || /* Since glibc 2.19: */ _DEFAULT_SOURCE
  64     || /* Glibc versions <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE
  65 .RE
  66 .ad b
  67 .SH DESCRIPTION
  68 These functions return the (real) cube root of
  69 .IR x .
  70 This function cannot fail; every representable real value has a
  71 representable real cube root.
  72 .SH RETURN VALUE
  73 These functions return the cube root of
  74 .IR x .
  75 .PP
  76 If
  77 .I x
  78 is +0, \-0, positive infinity, negative infinity, or NaN,
  79 .I x
  80 is returned.
  81 .SH ERRORS
  82 No errors occur.
  83 .SH ATTRIBUTES
  84 For an explanation of the terms used in this section, see
  85 .BR attributes (7).
  86 .TS
  87 allbox;
  88 lbw24 lb lb
  89 l l l.
  90 Interface       Attribute       Value
  91 T{
  92 .BR cbrt (),
  93 .BR cbrtf (),
  94 .BR cbrtl ()
  95 T}      Thread safety   MT-Safe
  96 .TE
  97 .SH CONFORMING TO
  98 C99, POSIX.1-2001, POSIX.1-2008.
  99 .\" .BR cbrt ()
 100 .\" was a GNU extension. It is now a C99 requirement.
 101 .SH SEE ALSO
 102 .BR pow (3),
 103 .BR sqrt (3)