From 635b2ad075fa0c2d11f57f817e944abfbcf442ed Mon Sep 17 00:00:00 2001
From: Pieter Wuille <sipa@ulyssis.org>
Date: Wed, 18 Apr 2012 02:12:21 +0200
Subject: [PATCH] Better combination formula

---
 combine.pl | 26 +++++++++++++++++++-------
 1 file changed, 19 insertions(+), 7 deletions(-)

diff --git a/combine.pl b/combine.pl
index 60112ac..6493724 100644
--- a/combine.pl
+++ b/combine.pl
@@ -5,29 +5,41 @@ use strict;
 sub loadFile {
   my ($file) = @_;
   my %ret;
-  my $min = 100000000;
+  my $max = 0;
   open FILE,$file;
   while (<FILE>) {
     my ($addr,$p2h,$p8h,$p1d,$p1w,$p1m) = split(/\s+/,$_);
     if ($p1m =~ /\A([1-9.]+)%\Z/) {
-      my $x = log($1*0.01)/log(0.5);
-      $min=$x if ($x < $min);
+      my $x = $1*0.01;
+      $max=$x if ($x > $max);
       $ret{$addr} = $x;
     }
   }
   for my $k (keys %ret) {
-    $ret{$k} -= $min;
+    $ret{$k} /= $max;
   }
   close FILE;
   return \%ret;
 }
 
+sub merge {
+  my ($a,$b) = @_;
+  return 1-(1-$a)*(1-$b);
+}
+
 sub combine {
   my ($f1,$f2) = @_;
   my %ret;
   for my $k1 (keys %{$f1}) {
     if (defined $f2->{$k1}) {
-      $ret{$k1} = $f1->{$k1} + $f2->{$k1};
+      $ret{$k1} = merge($f1->{$k1}, $f2->{$k1});
+    } else {
+      $ret{$k1} = merge($f1->{$k1}, 0);
+    }
+  }
+  for my $k2 (keys %{$f2}) {
+    if (!defined $f1->{$k2}) {
+      $ret{$k2} = merge(0, $f2->{$k2});
     }
   }
   return \%ret;
@@ -45,9 +57,9 @@ for my $file (@ARGV) {
   $n++;
 }
 
-for my $addr (sort { $res->{$a} <=> $res->{$b} } (keys %{$res})) {
+for my $addr (sort { $res->{$b} <=> $res->{$a} } (keys %{$res})) {
   if ($addr =~ /\A(\d+)\.(\d+)\.(\d+)\.(\d+):8333/) {
     my $a = $1*0x1000000 + $2*0x10000 + $3*0x100 + $4;
-    printf "0x%08x %s %g%%\n",$a,$addr,exp(log(0.5)*$res->{$addr}/$n)*100;
+    printf "0x%08x %s %g%%\n",$a,$addr,(1-((1-$res->{$addr}) ** (1/$n)))*100;
   }
 }