我正在尝试计算每个选举候选人（特别是 Stack Overflow 2014 版主选举）的第一、第二和第三选择票数。我下载了数据文件并打开了它。根据我对文件格式的基本解释，我编写了一个 PHP 脚本来计算选票：
<?php
$lines = file("stackoverflow-com-2014-election-results.blt");
unset($lines[0]);
$ballots = 0;
$first = array();
$second = array();
$third = array();
for ($i = 1;; $i++) {
$line = explode(" ", trim($lines[$i]));
if ($line[0] != 1) break;
$ballots++;
@$first[$line[1]]++;
@$second[$line[2]]++;
@$third[$line[3]]++;
}
$names = array();
for ($i++; $i < count($lines); $i++) {
$names[count($names) + 1] = trim(trim($lines[$i]), '"');
}
printf("%20s%8s%8s%8s%8s\n", "Name", "1st", "2nd", "3rd", "Total");
print(str_repeat("-", 52) . "\n");
foreach ($names as $id => $name) {
printf("%20s%8s%8s%8s%8s\n", $name,
$first[$id], $second[$id], $third[$id],
$first[$id] + $second[$id] + $third[$id]);
}
print(str_repeat("-", 52) . "\n");
printf("Ballots: %d\n", $ballots);
当我在命令行运行它时，它会打印这个表：
Name 1st 2nd 3rd Total
----------------------------------------------------
Undo 1358 1425 1814 4597
bluefeet 3352 3148 2287 8787
0x7fffffff 1932 2147 2159 6238
Bohemian 5678 2935 2415 11028
Jon Clements 1531 1527 1618 4676
Doorknob 1165 1720 1753 4638
Raghav Sood 1358 1565 1571 4494
Siddharth Rout 1732 1872 1866 5470
Matt 1381 1988 2009 5378
meagar 1903 2382 2881 7166
----------------------------------------------------
Ballots: 21571
我的问题是当我在同一个文件上运行它时，我无法让它与 OpenSTV 所说的相匹配。“第一选择的数量”都略有不同：
Ballot file contains 21571 non-empty ballots.
Counting votes for Stack Overflow Moderator Election 2014 using Meek STV.
10 candidates running for 3 seats.
R|Undo |bluefeet |0x7fffffff |Bohemian |Jon Clements
| | | | |
|--------------+--------------+--------------+--------------+--------------
|Doorknob |Raghav Sood |Siddharth Rout|Matt |meagar
| | | | |
|--------------+--------------+--------------+--------------+--------------
|Exhausted |Surplus |Threshold
| | |
=============================================================================
1| 1379.000000| 3372.000000| 1951.000000| 5707.000000| 1545.000000
| 1181.000000| 1375.000000| 1749.000000| 1389.000000| 1923.000000
| 0.000000| 314.249999| 5392.750001
|--------------------------------------------------------------------------
| Count of first choices. Candidate Bohemian has reached the threshold and
| is elected.
=============================================================================
[...]
我究竟做错了什么？或者 OpenSTV 有什么不同？
更新：我的脚本被破坏了，因为它没有考虑到一些用第二或第三选择编码的行，而没有设置先前的选择。我猜这是由于选举中的用户有时会取消选择先前的选择造成的：在选择了两个候选人之后，取消选择第一选择的候选人应该将唯一剩余的选定候选人视为用户的首选。
固定版本：
<?php
$lines = file("stackoverflow-com-2014-election-results.blt");
$line = explode(" ", trim($lines[0]));
$numCandidates = $line[0];
$numChoices = $line[1];
$choiceVotes = array_fill(1, $numChoices, array_fill(1, $numCandidates, 0));
$totalBallots = 0;
for ($i = 1;; $i++) {
$line = explode(" ", trim($lines[$i]));
if ($line[0] == 0) break;
$totalBallots++;
for ($j = 1, $k = 1; $j <= $numChoices; $j++) {
if ($line[$j] != 0) $choiceVotes[$k++][$line[$j]]++;
}
}
$names = array();
for ($j = 1; $j <= $numCandidates; $j++) {
$names[$j] = trim(trim($lines[$j + $i]), '"');
}
$rowFormat = "%20s" . str_repeat("%8s", $numChoices) . "%8s\n";
$separator = str_repeat("-", 20 + (8 * $numChoices) + 8) . "\n";
$row = array("Name");
for ($i = 1; $i <= $numChoices; $i++) $row[] = $i . gmdate('S', $i * 86400 - 1);
$row[] = "Total";
vprintf($rowFormat, $row);
print $separator;
foreach ($names as $id => $name) {
$row = array($name);
$candidateTotal = 0;
for ($i = 1; $i <= $numChoices; $i++) {
$votes = $choiceVotes[$i][$id];
$row[] = $votes;
$candidateTotal += $votes;
}
$row[] = $candidateTotal;
vprintf($rowFormat, $row);
}
print $separator;
printf("Ballots: %d\n", $totalBallots);
