i'm working on a perl script and i need a very specific random number generator.

what i have right now is multrand. it returns a random number between x/y and x*y, with the median result being x. half the time less than x, half the time, greater than x.

i want to build a sub that returns a random in the same range, but with the result more likely to be closer to x.

with a simple random, i'd just run the sub z times and return result/z. graph the results of that, and you get a bell curve.

the results/z method won't work here because i still want the results to be half the time less than x and half the time greater than x.

any ideas?

sub multrand {
        my ( $inmed, $inmult ) = @_;
        my $randreturn = 0;
        # $randtemp is used to determine if result will be more than, 
+less than, or equal to original
        my $randtemp = int(rand($inmed * 2));
        if ( $randtemp > $inmed ) {
                # $randreturn can be up to $inmed * $inmult
                $randreturn = int(rand(($inmed*$inmult)-$inmed)) + int
+($inmed);
        } elsif ( $randtemp < $inmed ) {
                # $randreturn can be as little as $inmed / $inmult
                $randreturn = int(rand($inmed*(1-(1/$inmult)))) + int(
+$inmed*(1/$inmult));
        } else {
                $randreturn = $inmed;
        }

        if ( $debug > 2 ) {
                print "$randreturn\n";
        }
        return $randreturn;
}

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In reply to custom random number generator by Anonymous Monk

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