private static Dictionary <double, Dictionary <double, DeviationObject> > AddRatingUpdateDeviations(Dictionary <int, Dictionary <int, double> > data, Dictionary <double, Dictionary <double, DeviationObject> > deviationsDictionary, int userId)
{
var user = data[userId];
var userRatedList = user.Keys.ToList();
//Update deviations after a new rating has been added by a user
foreach (var ratingId in userRatedList)
{
var deviation = Slope.GenerateDeviationObject(data, userId, ratingId);
deviationsDictionary[userId][ratingId] = Slope.GenerateDeviationObject(data, userId, ratingId);
deviationsDictionary[ratingId][userId] = new DeviationObject {
AmountOfRatings = deviation.AmountOfRatings, Deviation = deviation.Deviation * -1
};
}
return(deviationsDictionary);
}
private static Dictionary <int, Dictionary <int, DeviationObject> > GenerateDeviationsDictionary(Dictionary <int, Dictionary <int, double> > data, int[] uniqueIds)
{
var deviations = new Dictionary <int, Dictionary <int, DeviationObject> >();
//Loop over half the data and calulate the deviations
for (int i = 0; i < uniqueIds.Length; i++)
{
//Add a new row
deviations.Add(uniqueIds[i], new Dictionary <int, DeviationObject>());
for (int j = i; j < uniqueIds.Length; j++)
{
//Skip comparing the item to itself
if (i == j)
{
deviations[uniqueIds[i]].Add(uniqueIds[j], new DeviationObject());
continue;
}
//Add the deviation values at the correct index
deviations[uniqueIds[i]].Add(uniqueIds[j], Slope.GenerateDeviationObject(data, uniqueIds[i], uniqueIds[j]));
}
}
//Loop over the other half and inverse the deviation values
for (int a = 1; a < uniqueIds.Length; a++)
{
for (int b = 0; b < a; b++)
{
if (a == b)
{
continue;
}
var deviationObject = deviations[uniqueIds[b]][uniqueIds[a]];
var newDeviationObject = new DeviationObject()
{
AmountOfRatings = deviationObject.AmountOfRatings,
Deviation = deviationObject.Deviation * -1
};
deviations[uniqueIds[a]].Add(uniqueIds[b], newDeviationObject);
}
}
return(deviations);
}