public void Should_Generate_All_Possible_Pairings()
{
var generator = new SwissRankingEngine(new SwissStatisticsProvider());
var players = Enumerable
.Range(0, 26)
.Select(number => new String(new[] { (char)('a' + number) }))
.Select(name => new Player(name, null));
// Careful with the playerCount. 12 will take almost a minute to execute.
for(int playerCount = 2; playerCount <= 10; playerCount += 2)
{
var matchSets = generator.GeneratePairedMatches(players.Take(playerCount), Enumerable.Empty<MatchResult>(), 1);
var uniquePairings = matchSets
.Select(matchSet => matchSet
.Select(match => match
.Players
.OrderBy(player => player.Identifier)
.Select(player => player.Identifier)
)
.Select(playerIdentifiers => String.Join("-", playerIdentifiers))
.OrderBy(pairing => pairing)
)
.Select(playerIdentifiers => String.Join("|", playerIdentifiers))
.OrderBy(matchSetPairings => matchSetPairings)
.Distinct()
.ToArray();
// Expected number of pairings is (2n - 1)!! where n = playerCount / 2
// See http://en.wikipedia.org/wiki/Perfect_matching and http://en.wikipedia.org/wiki/Double_factorial for reasoning
// See http://mathworld.wolfram.com/DoubleFactorial.html for the definition of (2n - 1)!! used here
var expectedUniquePairings = (int)(Factorial(playerCount) / (Math.Pow(2, playerCount / 2) * Factorial(playerCount / 2)));
var actualUniquePairings = uniquePairings.Count();
Assert.Equal(expectedUniquePairings, actualUniquePairings);
}
}
public void Should_Generate_All_Possible_Pairings()
{
var generator = new SwissRankingEngine(new SwissStatisticsProvider());
var players = Enumerable
.Range(0, 26)
.Select(number => new String(new[] { (char)('a' + number) }))
.Select(name => new Player(name, null));
// Careful with the playerCount. 12 will take almost a minute to execute.
for (int playerCount = 2; playerCount <= 10; playerCount += 2)
{
var matchSets = generator.GeneratePairedMatches(players.Take(playerCount), Enumerable.Empty <MatchResult>(), 1);
var uniquePairings = matchSets
.Select(matchSet => matchSet
.Select(match => match
.Players
.OrderBy(player => player.Identifier)
.Select(player => player.Identifier)
)
.Select(playerIdentifiers => String.Join("-", playerIdentifiers))
.OrderBy(pairing => pairing)
)
.Select(playerIdentifiers => String.Join("|", playerIdentifiers))
.OrderBy(matchSetPairings => matchSetPairings)
.Distinct()
.ToArray();
// Expected number of pairings is (2n - 1)!! where n = playerCount / 2
// See http://en.wikipedia.org/wiki/Perfect_matching and http://en.wikipedia.org/wiki/Double_factorial for reasoning
// See http://mathworld.wolfram.com/DoubleFactorial.html for the definition of (2n - 1)!! used here
var expectedUniquePairings = (int)(Factorial(playerCount) / (Math.Pow(2, playerCount / 2) * Factorial(playerCount / 2)));
var actualUniquePairings = uniquePairings.Count();
Assert.Equal(expectedUniquePairings, actualUniquePairings);
}
}
