round-robin

Round-robin schedule generation reference implementation for PHP 7 licensed under the MIT license

Features

• Efficient schedule generation enabled by an efficient round-robin rotation function
• Ability to generate an arbitrary number of rounds
• Support for any number of teams by adding a bye for odd-numbered team counts
• Simple, concise implementation for easy analysis of the algorithm
• Unit tested
• Documented
• Modern PHP 7 code
• Object-oriented and procedural APIs

Basic Usage

Generating Common Schedules

Generate a random schedule where each player meets every other player once:

$teams = ['The 1st', '2 Good', 'We 3', '4ward'];
$scheduleBuilder = new ScheduleBuilder($teams);
$schedule = $scheduleBuilder->build();

or

$teams = ['The 1st', '2 Good', 'We 3', '4ward'];
$schedule = schedule($teams);

Generate a random home-away schedule where each player meets every other player twice, once at home and once away, using the $rounds integer parameter:

$teams = ['The 1st', '2 Good', 'We 3', '4ward'];
$rounds = (($count = count($teams)) % 2 === 0 ? $count - 1 : $count) * 2;
$scheduleBuilder = new ScheduleBuilder($teams, $rounds);
$schedule = $scheduleBuilder->build();

or

$teams = ['The 1st', '2 Good', 'We 3', '4ward'];
$rounds = (($count = count($teams)) % 2 === 0 ? $count - 1 : $count) * 2;
$schedule = schedule($teams, $rounds);

Generate a schedule without randomly shuffling the teams using the $shuffle boolean parameter:

$teams = ['The 1st', '2 Good', 'We 3', '4ward'];
$scheduleBuilder = new ScheduleBuilder($teams);
$scheduleBuilder->doNotShuffle();
$schedule = $scheduleBuilder->build();

or

$teams = ['The 1st', '2 Good', 'We 3', '4ward'];
$schedule = schedule($teams, null, false);

Use your own seed with the $seed integer parameter for predetermined shuffling:

$teams = ['The 1st', '2 Good', 'We 3', '4ward'];
$scheduleBuilder = new ScheduleBuilder($teams);
$scheduleBuilder->shuffle(89);
$schedule = $scheduleBuilder->build();

or

$teams = ['The 1st', '2 Good', 'We 3', '4ward'];
$schedule = schedule($teams, null, true, 89);

Looping Through A Schedule

Looping Through the Full Schedule

Setup:

$teams = ['The 1st', '2 Good', 'We 3', '4ward'];
$schedule = schedule($teams, null, true, 89);

or

$scheduleBuilder = new ScheduleBuilder();
$scheduleBuilder->setTeams($teams);
$scheduleBuilder->setRounds(10);
$scheduleBuilder->doNotShuffle();
$schedule = $scheduleBuilder->build();

Loop through:

<?php foreach($schedule as $round => $matchups){ ?>
    <h3>Round <?=$round?></h3>
    <ul>
    <?php foreach($matchups as $matchup) { ?>
        <li><?=$matchup[0] ?? '*BYE*'?> vs. <?=$matchup[1] ?? '*BYE*'?></li>
    <?php } ?>
    </ul>
<?php } ?>

Looping Through Team Schedules

<?php

$scheduleBuilder = new ScheduleBuilder($teams, 10);
$scheduleBuilder->shuffle(18);
$schedule = $scheduleBuilder->build();
?>


<?php foreach($teams as $team) { ?>
    <h3><?=$team?></h3>
    <ol>
    <?php foreach($schedule($team) as $contest) { ?>
        <li><?=(($contest['home'] ? '' : '@').($contest['team'] ?? '*BYE*'))?></li>
    <?php } ?>
    </ol>
<?php } ?>

License

MIT License

Author

Michael P. Nitowski <[email protected]>