return teams_to_idx;
}
-function partition_by_beat(games, teams)
+function partition_by_beat(teams, fill_beatmatrix)
{
// Head-to-head score by way of components. First construct the beat matrix.
let n = teams.length;
beat[i][j] = 0;
}
}
- for (let i = 0; i < games.length; ++i) {
- let idx1 = teams_to_idx[games[i].name1];
- let idx2 = teams_to_idx[games[i].name2];
- if (idx1 !== undefined && idx2 !== undefined) {
- if (games[i].score1 > games[i].score2) {
- beat[idx1][idx2] = 1;
- }
- if (games[i].score1 < games[i].score2) {
- beat[idx2][idx1] = 1;
- }
- }
- }
+ fill_beatmatrix(beat, teams_to_idx);
// Floyd-Warshall for transitive closure.
for (let k = 0; k < n; ++k) {
for (let i = 0; i < n; ++i) {
}
let result = [];
if (better_than_pivot.length > 0) {
- result = partition_by_beat(games, better_than_pivot);
+ result = partition_by_beat(better_than_pivot, fill_beatmatrix);
}
result.push(equal); // Obviously can't be partitioned further.
if (worse_than_pivot.length > 0) {
- result = result.concat(partition_by_beat(games, worse_than_pivot));
+ result = result.concat(partition_by_beat(worse_than_pivot, fill_beatmatrix));
}
return result;
}
}
// Rule #1: Head-to-head wins.
- let beat_parts = partition_by_beat(games, teams);
+ let num_relevant_games = 0;
+ let beat_parts = partition_by_beat(teams, function(beat, teams_to_idx) {
+ for (let i = 0; i < games.length; ++i) {
+ let idx1 = teams_to_idx[games[i].name1];
+ let idx2 = teams_to_idx[games[i].name2];
+ if (idx1 !== undefined && idx2 !== undefined) {
+ if (games[i].score1 > games[i].score2) {
+ beat[idx1][idx2] = 1;
+ ++num_relevant_games;
+ } else if (games[i].score1 < games[i].score2) {
+ beat[idx2][idx1] = 1;
+ ++num_relevant_games;
+ }
+ }
+ }
+ });
if (beat_parts.length > 1) {
tiebreakers.push(explain_tiebreaker(beat_parts, 'head-to-head'));
return subrank_partitions(games, beat_parts, start_rank, tiebreakers);
return subrank_partitions(games, nplayed_parts, start_rank, tiebreakers);
}
- // Rule #3: Head-to-head goal difference.
+ // Rule #3: Head-to-head goal difference (if all have played).
let teams_to_idx = make_teams_to_idx(teams);
- for (let i = 0; i < teams.length; i++) {
- teams[i].h2h_gd = 0;
- teams[i].h2h_goals = 0;
+ if (num_relevant_games >= teams.length * (teams.length - 1) / 2) {
+ for (let i = 0; i < teams.length; i++) {
+ teams[i].h2h_gd = 0;
+ teams[i].h2h_goals = 0;
+ }
+ for (let i = 0; i < games.length; ++i) {
+ let idx1 = teams_to_idx[games[i].name1];
+ let idx2 = teams_to_idx[games[i].name2];
+ if (idx1 !== undefined && idx2 !== undefined &&
+ !isNaN(games[i].score1) && !isNaN(games[i].score2)) {
+ teams[idx1].h2h_gd += games[i].score1;
+ teams[idx1].h2h_gd -= games[i].score2;
+ teams[idx2].h2h_gd += games[i].score2;
+ teams[idx2].h2h_gd -= games[i].score1;
+
+ teams[idx1].h2h_goals += games[i].score1;
+ teams[idx2].h2h_goals += games[i].score2;
+ }
+ }
+ let h2h_gd_parts = partition(teams, function(a, b) { return b.h2h_gd - a.h2h_gd });
+ if (h2h_gd_parts.length > 1) {
+ tiebreakers.push(explain_tiebreaker(h2h_gd_parts, 'head-to-head goal difference'));
+ return subrank_partitions(games, h2h_gd_parts, start_rank, tiebreakers);
+ }
}
+
+ // Rule #4: Goal difference against common opponents.
+ var results = {};
for (let i = 0; i < games.length; ++i) {
- let idx1 = teams_to_idx[games[i].name1];
- let idx2 = teams_to_idx[games[i].name2];
- if (idx1 !== undefined && idx2 !== undefined &&
- !isNaN(games[i].score1) && isNaN(games[i].score2)) {
- teams[idx1].h2h_gd += games[i].score1;
- teams[idx1].h2h_gd -= games[i].score2;
- teams[idx2].h2h_gd += games[i].score2;
- teams[idx2].h2h_gd -= games[i].score1;
-
- teams[idx1].h2h_goals += games[i].score1;
- teams[idx2].h2h_goals += games[i].score2;
+ if (results[games[i].name1] === undefined) {
+ results[games[i].name1] = {};
}
- }
- let h2h_gd_parts = partition(teams, function(a, b) { return b.h2h_gd - a.h2h_gd });
- if (h2h_gd_parts.length > 1) {
- tiebreakers.push(explain_tiebreaker(h2h_gd_parts, 'head-to-head goal difference'));
- return subrank_partitions(games, h2h_gd_parts, start_rank, tiebreakers);
- }
+ if (results[games[i].name2] === undefined) {
+ results[games[i].name2] = {};
+ }
+ results[games[i].name1][games[i].name2] = [ games[i].score1, games[i].score2 ];
+ results[games[i].name2][games[i].name1] = [ games[i].score2, games[i].score1 ];
+ }
+ let gd_parts = partition_by_beat(teams, function(beat, teams_to_idx) {
+ for (const team_i of Object.keys(teams_to_idx)) {
+ let i = teams_to_idx[team_i];
+ for (const team_j of Object.keys(teams_to_idx)) {
+ let j = teams_to_idx[team_j];
+ let results_i = results[team_i], results_j = results[team_j];
+ let gd_i = 0, gd_j = 0;
+
+ // See if the two teams have both played a third team k.
+ for (let k in results_i) {
+ if (!results_i.hasOwnProperty(k)) continue;
+ if (results_j[k] !== undefined) {
+ gd_i += results_i[k][0] - results_i[k][1];
+ gd_j += results_j[k][0] - results_j[k][1];
+ }
+ }
- // Rule #4: Global goal difference. (Well, not strictly, but good enough.)
- let gd_parts = partition(teams, function(a, b) { return b.gd - a.gd });
+ if (gd_i > gd_j) {
+ beat[i][j] = 1;
+ } else if (gd_i < gd_j) {
+ beat[j][i] = 1;
+ }
+ }
+ }
+ });
if (gd_parts.length > 1) {
- tiebreakers.push(explain_tiebreaker(gd_parts, 'overall goal difference'));
+ tiebreakers.push(explain_tiebreaker(gd_parts, 'goal difference versus common opponents'));
return subrank_partitions(games, gd_parts, start_rank, tiebreakers);
}
- // Rule #5: Head-to-head scored goals.
- let h2h_goals_parts = partition(teams, function(a, b) { return b.h2h_goals - a.h2h_goals });
- if (h2h_goals_parts.length > 1) {
- tiebreakers.push(explain_tiebreaker(h2h_goals_parts, 'head-to-head scored goals'));
- return subrank_partitions(games, h2h_goals_parts, start_rank, tiebreakers);
+ // Rule #5: Head-to-head scored goals (if all have played).
+ if (num_relevant_games >= teams.length * (teams.length - 1) / 2) {
+ let h2h_goals_parts = partition(teams, function(a, b) { return b.h2h_goals - a.h2h_goals });
+ if (h2h_goals_parts.length > 1) {
+ tiebreakers.push(explain_tiebreaker(h2h_goals_parts, 'head-to-head scored goals'));
+ return subrank_partitions(games, h2h_goals_parts, start_rank, tiebreakers);
+ }
}
- // Rule #6: Overall scored goals. (Same caveat as #4.)
- let goals_parts = partition(teams, function(a, b) { return b.goals - a.goals });
+ // Rule #6: Goals scored against common opponents.
+ let goals_parts = partition_by_beat(teams, function(beat, teams_to_idx) {
+ for (const team_i of Object.keys(teams_to_idx)) {
+ let i = teams_to_idx[team_i];
+ for (const team_j of Object.keys(teams_to_idx)) {
+ let j = teams_to_idx[team_j];
+ let results_i = results[team_i], results_j = results[team_j];
+ let goals_i = 0, goals_j = 0;
+
+ // See if the two teams have both played a third team k.
+ for (let k in results_i) {
+ if (!results_i.hasOwnProperty(k)) continue;
+ if (results_j[k] !== undefined) {
+ goals_i += results_i[k][0];
+ goals_j += results_j[k][0];
+ }
+ }
+
+ if (goals_i > goals_j) {
+ beat[i][j] = 1;
+ } else if (goals_i < goals_j) {
+ beat[j][i] = 1;
+ }
+ }
+ }
+ });
if (goals_parts.length > 1) {
- tiebreakers.push(explain_tiebreaker(goals_parts, 'scored goals'));
+ tiebreakers.push(explain_tiebreaker(goals_parts, 'goals scored against common opponents'));
return subrank_partitions(games, goals_parts, start_rank, tiebreakers);
}
projects / ultimatescore / blobdiff