I figure there must be a module to do this. Anyone know what it is? I wrote my own in the mean time: 
sub sum($) {
    my $listref = $_[0];
    my $sum = 0;
    map { $sum += $_ } @{$listref};
    return $sum;
}

sub avg($) {
    my $listref = $_[0];
    sum($listref)/@{$listref};
}

sub rms($) {
    my $listref = $_[0];
    sqrt(sum([map{(avg($listref)-$_)**2}@{$listref}])/@{$listref});
}

[download]
Pls comment.

"Argument is futile - you will be ignorralated!"

In reply to How do I get the root mean square of a list? by larryk

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