# to Debian Constitution A.6.
#
# usage: .../compute [<input files>...]
+# (uses stdin if none supplied)
#
-#
+# input files can be in any order and should contain lines like:
+#
+# <votername> :: <PREF>, (<PREF>=<PREF>), <PREF>, ....
+# V: <tallyprefs> <votername>
+# <ABBREV> = <description...>
+# <ABBREV> = <description...> [<rat>:<io>]
+# <ABBREV> = <description...> [default]
+# nodefault
+# quorum = <quorum>
+#
+# where
+#
+# <votername> is any non-whitespace characters
+#
+# <ABBREV> and <PREF> are abbreviations for choices on the ballot.
+# They must be ASCII alphanumeric. Numeric preferences are
+# not recommended as they are confusing (particularly when
+# tally sheets are in use).
+#
+# It is best to avoid FD, SQ and NOTA except for the default
+# option; if no default option is specified, it will default
+# to one of these unless a "nodefault" line is found.
+#
+# In the "::" form, the commas are optional. Either ( ) or = may
+# be used to indicate a set of equal preferences.
+#
+# <tallyprefs> is a tally sheet preference order: that is,
+# a single uppercase base36 digit for each ballot choice,
+# (in the order they were specified by "=" lines), giving
+# the voter's preference rank for that option. The numbers
+# need not be distinct or contiguous. "-" may be used for
+# unranked preferences.
+#
+# <rat>:<io> is the majority ratio for the option
+#
+# <quorum> is the quorum
+#
+# and also allowed are
+#
+# #-comments } all
+# blank lines } ignored
+# lines starting with whitespace }
use strict;
use utf8;
use autodie;
-use Data::Printer;
use Graph::Directed;
+use Graph::Writer::GraphViz;
binmode STDIN, 'encoding(UTF-8)';
binmode STDOUT, 'encoding(UTF-8)';
our $defcho;
our $quorum = 0;
+our $gfile;
+
+while (@ARGV && $ARGV[0] =~ /^-/) {
+ local $_ = shift @ARGV;
+ if (m/^--?$/) {
+ last;
+ } elsif (s/^-g//) {
+ $gfile = $_;
+ } else {
+ die "bad usage\n";
+ }
+}
+
sub addchoice {
my $choname = shift @_;
my $cho = $choices{$choname} = {
next if m/^\s*\#/;
next unless m/\S/;
next if m/^\s/;
- if (m/^([A-Z]+)\s*\=\s*(\S.*)$/) {
+ if (m/^([A-Z0-9]+)\s*\=\s*(\S.*)$/) {
my ($choname, $desc) = ($1,$2);
my $cho = addchoice($choname, Desc => $desc);
if ($desc =~ m/\[(\d+):(\d+)\]/) {
# Go through the voters and construct V(A,B)
-print "\nParsing \`simple' style ballots\n";
+print "\nParsing \`simple' style ballots\n# devotee-tally-begin\n"
+ if @invotes_cc;
# actually, we pre-parse them into @invotes_v
# since we want to show them as a tally sheet anyway
push @invotes_v, [ $vstr, $voter ];
}
+print "# devotee-tally-end\n"
+ if @invotes_cc;
+
print "\nDetermining default option\n";
if ($defcho && $defcho->{Index} > -1) {
last if $defcho;
}
if ($defcho) {
- print "guessed default option was: $choices[$defcho->{Index}]\n";
+ print "guessed default option: $choices[$defcho->{Index}]\n";
} else {
print "could not guess default option, assuming there is none\n";
}
my $defi = $defcho->{Index};
die "FD has smaj?!" if $defcho->{Smaj};
-print "\nParsing devotee tally sheet ballots\n";
+print "\nParsing devotee tally sheet ballots\n"
+ if @invotes_v > @invotes_cc;
foreach my $iv (@invotes_v) {
my ($votestr,$voter) = @$iv;
my $vchr = $vs[$ix];
if ($vchr eq '-') {
$vs[$ix] = 1000;
- } elsif ($vchr =~ m/[0-9a-z]/) {
+ } elsif ($vchr =~ m/[0-9A-Z]/) {
$vs[$ix] = ord($vchr);
} else {
die "bad vote char";
my $vad = scalar @{ $vab[$i][$defi] };
my $vda = scalar @{ $vab[$defi][$i] };
next if $vad * $majr->[1] > $vda * $majr->[0];
- drop $i, "majority ratio ($vad * $majr->[1] <= $vda * $majr->[0])";
+ drop $i, "majority ratio ($vad:$vda <= $majr->[1]:$majr->[0])";
}
}
return grep { !$ch[$_]{Dropped} } (0..$#ch);
}
-foreach my $ia (chremain()) {
+foreach my $ia (0..$#ch) {
$defeats->add_vertex($choices[$ia]);
- foreach my $ib (chremain()) {
+ foreach my $ib (0..$#ch) {
my $vab = scalar @{ $vab[$ia][$ib] };
my $vba = scalar @{ $vab[$ib][$ia] };
next unless $vab > $vba;
print "defeat: $choices[$ia] beats $choices[$ib]",
" ($vab > $vba = +$diff)\n";
$defeats->add_edge($choices[$ia],$choices[$ib]);
+ my $label = "$diff($vab:$vba)";
+ if (@invotes_v < 10) {
+ $label .= "\n". join ' ', @{ $vab[$ia][$ib] };
+ $label .= "\n/". join ' ', @{ $vab[$ib][$ia] };
+ }
+ $defeats->set_edge_attribute($choices[$ia],$choices[$ib],
+ label => $label);
}
}
return 0;
}
+our $showg = $defeats->deep_copy();
+
+foreach my $ix (0..$#ch) {
+ my $cho = $ch[$ix];
+ next unless $cho->{Dropped};
+ $defeats->delete_vertex($choices[$ix]);
+}
+
our $schwartz;
-for (;;) {
+for (my $dropiter = 1; ; $dropiter++) {
# loop from A6(5)
print "defeats graph: $defeats\n";
- print "\nTransitive closure A.6(5)\n";
+ print "\nTransitive closure A.6(5) (iteration $dropiter)\n";
my $tdefeats = $defeats->transitive_closure();
+ # this makes the debugging output prettier
+ foreach my $ch (@choices) {
+ $tdefeats->delete_edge($ch,$ch);
+ }
print "closure graph: $tdefeats\n";
print "\nSchwartz set A.6(6)\n";
my ($ca,$cb) = @$weakest;
print "a weakest defeat is $ca > $cb\n";
$defeats->delete_edge($ca,$cb);
+ my $label = $showg->get_edge_attribute($ca,$cb,'label');
+ $label .= "\ndropped - weakest in iter.$dropiter";
+ $showg->set_edge_attribute($ca,$cb,'label',$label);
+ $showg->set_edge_attribute($ca,$cb,'style','dotted');
+ $showg->set_edge_attribute($ca,$cb,'graphviz',{constraint=>0});
}
print "\nDefeats within the Schwartz set, go round again\n";
print "no defeats within the Schwartz set\n";
print "final schwartz set:\n\n";
+my $winxlabel;
if ($schwartz->vertices() == 1) {
print "WINNER IS:\n";
+ $winxlabel = "winner";
} else {
print "WINNER IS ONE OF (CASTING VOTE DECIDES):\n";
+ $winxlabel = "potential winner";
}
printf " %-5s %s\n", $_, $choices{$_}{Desc}
foreach ($schwartz->vertices());
+if (defined $gfile) {
+ foreach my $cho (values %choices) {
+ my $chn = $choices[$cho->{Index}];
+ my $label = "$chn\n$cho->{Desc}";
+ if ($cho->{Dropped}) {
+ $label .= "\nDropped: $cho->{Dropped}";
+ }
+ if ($schwartz->has_vertex($chn)) {
+ $label .= "\n$winxlabel";
+ }
+ $showg->set_vertex_attribute($chn, 'label', $label);
+ }
+
+ my $gwriter = new Graph::Writer::GraphViz -format => 'ps';
+ $gwriter->write_graph($showg, $gfile);
+}
+
print ".\n";
#p %choices;
~ian / appendix-a6.git / blobdiff