There's the code from the Perl Cookbook:

**UPDATE: here is a node that already mentions it (and the weight_to_dist sub that I didn't put here). 
###########################
#from Perl Cookbook 2.10
#take in a hash and via a weighted random, pick one of the 
#keys based on the value and return it
###########################
sub weighted_rand {
    my %dist = @_;
    my ($key, $weight);
    my $rand;

    while (1) { # to avoid floating point inaccuracies
        $rand = rand;
        while ( ($key, $weight) = each %dist ) {
            return $key if ($rand -= $weight) < 0;
        }
    }
}
###########################

[download]


------------------------------------
There are some odd things afoot now,
in the Villa Straylight.

In reply to Re: Weighted random numbers generator by AssFace
in thread Weighted random numbers generator by spurperl

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