public EloResult CalcElo(int playerOneElo, int playerTwoElo, MatchWinner winner)
{
// A2 = A1 + 32 (G-(1/(1+10 ** ((B1-A1)/400))))
float G = 0;
float A1 = System.Convert.ToSingle(playerOneElo);
float B1 = System.Convert.ToSingle(playerTwoElo);
if (winner == MatchWinner.PlayerOne)
{
G = 1;
}
if (winner == MatchWinner.PlayerTwo)
{
G = 0;
}
double changeValue = factor * (G - (1 / (1 + System.Math.Pow(10, ((B1 - A1) / divisor)))));
int changeValueInt = System.Convert.ToInt32(changeValue);
EloResult result = new EloResult();
if (winner == MatchWinner.PlayerOne)
{
result.PlayerOneElo = playerOneElo + changeValueInt;
result.PlayerTwoElo = playerTwoElo - changeValueInt;
}
if (winner == MatchWinner.PlayerTwo)
{
result.PlayerOneElo = playerOneElo + changeValueInt;
result.PlayerTwoElo = playerTwoElo - changeValueInt;
}
result.changeValue = changeValueInt;
return(result);
}
private EloPlayerMatchResultVM GetEloPlayerMatchResultVM(EloResult eloResult)
{
return(new EloPlayerMatchResultVM()
{
OpeningRating = eloResult.OpeningRating,
TransformedRating = eloResult.TransformedRating,
ExpectedScore = eloResult.ExpectedScore,
ActualScore = eloResult.ActualScore,
KFactor = eloResult.KFactor,
ClosingRating = eloResult.ClosingRating
});
}
private EloResult CalculateEloRatings(int playerId, int opponentId, bool winner, AllTimeCompetition competition)
{
var ratings = new EloResult();
var mostRecentRating = GetMatchParticipations(true)
.Where(mp => mp.PlayerID == playerId)
.FirstOrDefault();
var opponentRating = GetMatchParticipations(true)
.Where(mp => mp.PlayerID == opponentId)
.FirstOrDefault();
var openingRating = (mostRecentRating == null) ? RATING_SEED_VALUE : mostRecentRating.AllTimeCompetitionResult.ClosingRating;
var opptRating = (opponentRating == null) ? RATING_SEED_VALUE : opponentRating.AllTimeCompetitionResult.ClosingRating;
return(_ratingCalc.CalculateRatings(openingRating, opptRating, winner, competition.KFactor));
}
public EloResult CalculateRatings(int playerRating, int opponentRating, bool playerWon, int KFactor)
{
var ratings = new EloResult();
ratings.OpeningRating = playerRating;
ratings.TransformedRating = Math.Pow(10, ((double)ratings.OpeningRating / ELO_N_VALUE));
ratings.OpponentRating = opponentRating;
ratings.OpponentTransformedRating = Math.Pow(10, (double)ratings.OpponentRating / ELO_N_VALUE);
ratings.ExpectedScore = ratings.TransformedRating / (ratings.TransformedRating + ratings.OpponentTransformedRating);
ratings.KFactor = KFactor;
ratings.ActualScore = playerWon ? 1 : 0;
ratings.ClosingRating = Convert.ToInt32(Math.Round(ratings.OpeningRating + ratings.KFactor * (ratings.ActualScore - ratings.ExpectedScore)));
return(ratings);
}