Some of the coolest programs are the ones with random results... russian roullette, initial placement in Life, etc.

I wanted to see how close to even rand() would get over a large sample size, so I ran 100 million tests, and published the results.

If this gets moved to Code Catacombs, that's fine by me. It's not exactly cool, but it is cool by extension. :)

Also, if someone would like to comment on how it could be made more efficient, that would be awesome! I'm specifically interested in the while block, because it's the workhorse, though other comments are good too.

Code:

#!/usr/bin/perl -w
use strict;

my ($counter, $tests) = (0, 100_000_000);
my %results;

my $rand;                #declare once, save time
while ($counter++ < $tests) {        #not creating with .. operator, m
+em efficient
    $rand = int(rand(10) + 1);
    $results{$rand}++;
}

my $total;
$total += $_ for values %results;    #only 10 results possible

print "\n\n";
print "Total\t$total\n\n";
print "$_:\t$results{$_}\t\t" . $results{$_} / $total  * 100 . "\n" 
                        for sort {$a <=> $b} keys %results;
print "\n\n";
[download]

Output:

Total   100000000
 
1:      10003440                10.00344
2:      9996091         9.996091
3:      10004370                10.00437
4:      9996926         9.996926
5:      10000607                10.000607
6:      9998471         9.998471
7:      10002412                10.002412
8:      9997738         9.997738
9:      9999782         9.999782
10:     10000163                10.000163