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'\" t
.\" Copyright 1995 Jim Van Zandt <jrv@vanzandt.mv.com>
.\"
.\" SPDX-License-Identifier: Linux-man-pages-copyleft
.\"
.\" changed `square root' into `cube root' - aeb, 950919
.\"
.\" Modified 2002-07-27 Walter Harms
.\" (walter.harms@informatik.uni-oldenburg.de)
.\"
.TH cbrt 3 2024-05-02 "Linux man-pages (unreleased)"
.SH NAME
cbrt, cbrtf, cbrtl \- cube root function
.SH LIBRARY
Math library
.RI ( libm ", " \-lm )
.SH SYNOPSIS
.nf
.B #include <math.h>
.P
.BI "double cbrt(double " x );
.BI "float cbrtf(float " x );
.BI "long double cbrtl(long double " x );
.fi
.P
.RS -4
Feature Test Macro Requirements for glibc (see
.BR feature_test_macros (7)):
.RE
.P
.BR cbrt ():
.nf
_ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
|| _XOPEN_SOURCE >= 500
.\" || _XOPEN_SOURCE && _XOPEN_SOURCE_EXTENDED
|| /* Since glibc 2.19: */ _DEFAULT_SOURCE
|| /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE
.fi
.P
.BR cbrtf (),
.BR cbrtl ():
.nf
_ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
|| /* Since glibc 2.19: */ _DEFAULT_SOURCE
|| /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE
.fi
.SH DESCRIPTION
These functions return the (real) cube root of
.IR x .
This function cannot fail;
every representable real value
has a real cube root,
and rounding it to a representable value
never causes overflow nor underflow.
.SH RETURN VALUE
These functions return the cube root of
.IR x .
.P
If
.I x
is +0, \-0, positive infinity, negative infinity, or NaN,
.I x
is returned.
.SH ERRORS
No errors occur.
.SH ATTRIBUTES
For an explanation of the terms used in this section, see
.BR attributes (7).
.TS
allbox;
lbx lb lb
l l l.
Interface Attribute Value
T{
.na
.nh
.BR cbrt (),
.BR cbrtf (),
.BR cbrtl ()
T} Thread safety MT-Safe
.TE
.SH STANDARDS
C11, POSIX.1-2008.
.SH HISTORY
C99, POSIX.1-2001.
.\" .BR cbrt ()
.\" was a GNU extension. It is now a C99 requirement.
.SH SEE ALSO
.BR pow (3),
.BR sqrt (3)
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