wip

[appendix-a6.git] / parse

diff --git a/parse b/parse
index adb3d7df3ad1062d5759645458f61b9513087644..13fe2f23395fabb16bb0a9b15d3bc6496f9454ea 100755 (executable)
--- a/parse
+++ b/parse
@@ -27,6 +27,7 @@ while (<>) {
     s/\s+$//;
     next if m/^\s*\#/;
     next unless m/\S/;
+    next if m/^\s/;
     if (m/^([A-Z]+)\s*\=\s*(\S.*)$/) {
        my ($choname, $desc) = ($1,$2);
        my $cho = addchoice($choname, Desc => $desc);
@@ -57,6 +58,8 @@ our @vab;
 
 # Go through the voters and construct V(A,B)
 
+print "\nPreference matrix\n";
+
 foreach my $iv (@invotes) {
     my ($votestr,$voter) = @$iv;
     eval {
@@ -122,7 +125,7 @@ sub drop ($$) {
     $ch[$i]{Dropped} = $why;
 }
 
-print "# quorum A.6(2)\n";
+print "\nQuorum A.6(2) (quorum is $quorum)\n";
 
 foreach my $i (0..$#choices) {
     next if $ch[$i]{Dropped};
@@ -132,7 +135,7 @@ foreach my $i (0..$#choices) {
     drop $i, "quorum ($v < $quorum)";
 }
 
-print "# maj. ratio A.6(3)\n";
+print "\nMajority ratio A.6(3)\n";
 
 foreach my $i (0..$#choices) {
     next if $ch[$i]{Dropped};
@@ -145,66 +148,77 @@ foreach my $i (0..$#choices) {
     drop $i, "majority ratio ($vad * $majr->[1] <= $vda * $majr->[0])";
 }
 
-my $defeats = Graph::Directed->new; # A.6(4)
+print "\nDefeats A.6(4)\n";
+
+my $defeats = Graph::Directed->new;
 
 sub chremain () {
     return grep { !$ch[$_]{Dropped} } (0..$#ch);
 }
 
 foreach my $ia (chremain()) {
-    $defeats->add_vertex($ia);
+    $defeats->add_vertex($choices[$ia]);
     foreach my $ib (chremain()) {
        my $vab = scalar @{ $vab[$ia][$ib] };
        my $vba = scalar @{ $vab[$ib][$ia] };
        next unless $vab > $vba;
-       print "defeat: $choices[$ia] beats $choices[$ib] ($vab > $vba)\n";
-       $defeats->add_vertex($ia,$ib);
+       my $diff = $vab - $vba;
+       print "defeat: $choices[$ia] beats $choices[$ib]",
+           " ($vab > $vba: $diff)\n";
+       $defeats->add_edge($choices[$ia],$choices[$ib]);
     }
 }
 
+sub chvab ($$) {
+    my ($ca,$cb) = @_;
+    my $v = $vab[ $choices{$ca}{Index} ][ $choices{$cb}{Index} ];
+    return scalar @$v;
+}
+
 sub weaker ($$) {
     # A.6(7)(1)
     my ($def1,$def2) = @_;
-    my ($ia,$ix) = @$def1;
-    my ($ib,$iy) = @$def1;
-    return 1 if $vab[$ia][$ix] < $vab[$ib][$iy];
-    return 1 if $vab[$ia][$ix] == $vab[$ib][$iy]
-       && $vab[$ix][$ia] > $vab[$iy][$ib];
+    my ($ca,$cx) = @$def1;
+    my ($cb,$cy) = @$def1;
+    return 1 if chvab($ca, $cx) < chvab($cb, $cy);
+    return 1 if chvab($ca, $cx) == chvab($cb, $cy)
+       && chvab($cx, $ca) > chvab($cy, $cb);
     return 0;
 }
 
-print "defeats graph: $defeats\n";
-
 our $schwartz;
 
 for (;;) {
     # loop from A6(5)
 
-    print "# transitive closure A.6(5)\n";
+    print "defeats graph: $defeats\n";
+
+    print "\nTransitive closure A.6(5)\n";
 
     my $tdefeats = $defeats->transitive_closure();
 
     print "closure graph: $tdefeats\n";
 
-    print "# Schwartz set A.6(6)\n";
+    print "\nSchwartz set A.6(6)\n";
     
     $schwartz = $defeats->copy();
 
     foreach my $ia (chremain()) {
        foreach my $ib (chremain()) {
-           next if $tdefeats->has_edge($ia,$ib);
-           next if !$tdefeats->has_edge($ib,$ia);
+           next if $tdefeats->has_edge($choices[$ia],$choices[$ib]);
+           next if !$tdefeats->has_edge($choices[$ib],$choices[$ia]);
            print "not in Schwartz set: $choices[$ia] because $choices[$ib]\n";
-           $schwartz->delete_vertex($ia);
+           $schwartz->delete_vertex($choices[$ia]);
            last;
        }
     }
 
-    print "# dropping weakest defeats A.6(7)\n";
+    print "\nDropping weakest defeats A.6(7)\n";
 
     our @weakest = ();
 
     foreach my $edge ($schwartz->edges()) {
+#      print " considering @$edge\n";
        if (!@weakest) {
            # no weakest edges yet
        } elsif (weaker($edge, $weakest[0])) {
@@ -220,23 +234,30 @@ for (;;) {
     }
 
     last unless @weakest;
-    
-    printf "weakest defeats %d > %d", 
-       (scalar @{ $vab[$_->[0]][$_->[1]] }),
-       (scalar @{ $vab[$_->[1]][$_->[0]] });
+
+    my $w = $weakest[0];
+    printf "weakest defeats %d > %d\n", 
+        chvab($w->[0], $w->[1]),
+       chvab($w->[1], $w->[0]);
     foreach my $weakest (@weakest) {
-       my ($ia,$ib) = @$weakest;
-       print "weakest defeat $choices[$ia] > $choices[$ib]\n";
-       $defeats->delete_edge($ia,$ib);
+       my ($ca,$cb) = @$weakest;
+       print "weakest defeat $ca > $cb\n";
+       $defeats->delete_edge($ca,$cb);
     }
 
-    print "# defeats within the Schwartz set, round again\n";
+    print "defeats within the Schwartz set, round again\n";
 }
 
-print "# no defeats within the Schwartz set\n";
-print "FINAL SCHWARTZ SET:\n";
+print "no defeats within the Schwartz set\n";
+print "final schwartz set:\n\n";
+
+if ($schwartz->vertices() == 1) {
+    print "WINNER IS:\n";
+} else {
+    print "WINNER IS ONE OF (CASTING VOTE DECIDES):\n";
+}
 
-printf "    %-5s %s\n", $choices[$_], $ch[$_]{Desc}
+printf "    %-5s %s\n", $_, $choices{$_}{Desc}
     foreach ($schwartz->vertices());
 
 print ".\n";