return $dbh;
}
-# 10-9 is 0.60
-# 10-0 is 1.00
-sub find_score {
- my ($score1, $score2) = @_;
- if ($score1 == 10) {
- # yay, a win
- return 0.60 + 0.40 * (9.0-$score2)/9.0;
- }
- if ($score2 == 10) {
- # a loss
- return 0.40 - 0.40 * (9.0-$score1)/9.0;
- }
- die "Nobody won?";
-}
-
# c=8 => RD=50 moves to RD=350 over approx. five years
our $c = 8;
return $rd;
}
-our $q = log(10)/400.0;
-our $pi = 3.1415926535897932384626433832795;
-
-# computes a^b
-sub pow {
- my ($a, $b) = @_;
-
- # a^b = exp(log(a^b)) = exp(b log a)
- return exp($b * log($a));
-}
-
-sub g {
- my $rd = shift;
- return 1.0 / sqrt(1.0 + 3.0 * $q * $q * $rd * $rd / ($pi*$pi));
-}
-
-sub E {
- my ($r, $rating, $rd) = @_;
- return 1.0 / (1.0 + pow(10.0, -g($rd) * ($r - $rating) / 400.0));
-}
-
-sub dsq {
- my ($r, $rating, $rd) = @_;
- return 1.0 / ($q*$q * g($rd) * g($rd) * E($r, $rating, $rd) * (1 - E($r, $rating, $rd)));
-}
-
sub calc_rating {
my ($rating1, $rd1, $rating2, $rd2, $score1, $score2) = @_;
- my $s1 = find_score($score1, $score2);
- my $d1sq = dsq($rating1, $rating2, $rd2);
- my $newr1 = $rating1 + ($q / (1.0/($rd1*$rd1) + 1.0 / $d1sq)) * g($rd2) * ($s1 - E($rating1, $rating2, $rd2));
- my $newrd1 = sqrt(1.0 / (1.0 / ($rd1*$rd1) + 1.0 / $d1sq));
+ my $result = `/srv/foosball.sesse.net/foorank $rating1 $rd1 $rating2 $rd2 $score1 $score2`;
+ chomp $result;
+ my ($newr1, $newrd1) = split / /, $result;
$newrd1 = 30.0 if ($newrd1 < 30.0);