From: Steinar H. Gunderson <sesse@debian.org>
Date: Wed, 3 Oct 2007 20:44:46 +0000 (+0200)
Subject: Switch to FooRank!
X-Git-Url: https://git.sesse.net/?p=foosball;a=commitdiff_plain;h=62e8c1c8107d8d626d319c308518c9dcf170f501

Switch to FooRank!
---

diff --git a/foosball.pm b/foosball.pm
index 164b3e3..4fd318c 100644
--- a/foosball.pm
+++ b/foosball.pm
@@ -65,38 +65,11 @@ sub apply_aging {
 	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);