Which function for third root of number ?

Wampa has asked for the wisdom of the Perl Monks concerning the following question:

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Re: Which function for third root of number ? by Roy Johnson (Monsignor) on Jul 09, 2004 at 11:34 UTC
Use the fact that the `n`th root of `x` is `x` to the power of `1/n`: `27**(1/3)` [download] We're not really tightening our belts, it just feels that way because we're getting fatter.	[reply] [d/l] [select]
Re: Which function for third root of number ? by ysth (Canon) on Jul 09, 2004 at 11:37 UTC
`27 ** (1/3)`, which may cause some roundoff error.	[reply] [d/l]
Re^2: Which function for third root of number ? by xorl (Deacon) on Jul 09, 2004 at 15:04 UTC
If you're looking for perfect cubes .... `use POSIX qw(ceil floor); if (ceil($num 1/3) == floor($num 1/3)) { print $num . " is a cube of " $num ** 1/3; } else { print $num . " is not a perfect cube."; }` [download] Like all of my code the above is untested and comes with no warrenty implied or otherwise.	[reply] [d/l]
Re: Which function for third root of number ? by davidj (Priest) on Jul 09, 2004 at 11:39 UTC
Here's one way to do it (without having to use any module functions): `#!/usr/bin/perl use strict; my $a = 27 ** (1/3); # 1/3 represents cube root print "a = $a"; exit;` [download] output: `a = 3` [download] davidj	[reply] [d/l] [select]
Re^2: Which function for third root of number ? by Wampa (Hermit) on Jul 09, 2004 at 11:46 UTC
Thanks to all Programing in Embperl and all questions are related to Embperl. Excuse my bad English !!!	[reply]
Re^3: Which function for third root of number ? by Grygonos (Chaplain) on Jul 09, 2004 at 12:48 UTC
Have a look at My previous answer to this question Grygonos	[reply]
Re: Which function for third root of number ? by sleepingsquirrel (Chaplain) on Jul 09, 2004 at 16:55 UTC
`sub cbrt { return exp(log($_[0])/3) }` [download] -- All code is 100% tested and functional unless otherwise noted.	[reply] [d/l]