in reply to Calculating Nth root using perl.

Other than the snarky RTFM (Perl has an intrinsic exponentiation operator)

$x = $y ** (1/4) if $y > 0;

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 This is the revised code, in response to salva's and ikegami's comments 
if($y >= 0){
    $x = $y ** (1/4);
}else{
    undef($x);
    die "Even roots of negative numbers require complex arithmetic\n";
}

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While the 4th root of a negative number exists, I'm presuming you don't need to do complex arithmetic. If you do, you man want to check out Math::Complex, although it appears to be developmental.

emc

"Being forced to write comments actually improves code, because it is easier to fix a crock than to explain it. "
—G. Steele

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Re^2: Calculating Nth root using perl.
by salva (Canon) on May 09, 2006 at 18:31 UTC
    your code is not going to generate any error when $y < 0. That's usually a very bad thing!

    Just 

    $x = $y ** (1/4);

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    is better!
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[d/l]
[select]
      I agree (++). Error handling shouldn't be removed without being replaced. Either handle it (by throwing an exception, displaying a warning, returning a complex number, returning an error code, etc) or let Perl handle it (by dying).
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