public IActionResult Correlation(int id)
{
User user = _db.Users.FirstOrDefault(u => u.Id == id);
if (user == null)
{
return(NotFound());
}
List <User> users = _db.Users.Where(u => u.Id != id).ToList();
List <UserCoeff> userCoeffs = new List <UserCoeff>();
foreach (User u in users)
{
List <UserMark> usermarks1 = _db.UserMarks.Where(um => um.UserId == user.Id).ToList();
List <UserMark> usermarks2 = _db.UserMarks.Where(um => um.UserId == u.Id).ToList();
int lectionsNumber = _db.Lections.Count();
List <double> list1 = new double[lectionsNumber].ToList();
List <double> list2 = new double[lectionsNumber].ToList();
foreach (UserMark um in usermarks1)
{
list1[um.LectionId - 1] = um.Mark;
}
foreach (UserMark um in usermarks2)
{
list2[um.LectionId - 1] = um.Mark;
}
while (true)
{
int index1 = list1.IndexOf(0);
if (index1 != -1)
{
list1.RemoveAt(index1);
list2.RemoveAt(index1);
}
int index2 = list2.IndexOf(0);
if (index2 != -1)
{
list1.RemoveAt(index2);
list2.RemoveAt(index2);
}
if (index1 == -1 && index2 == -1)
{
break;
}
}
double coeff = CollaborationFilter.Correlation(list1.ToArray(), list2.ToArray());
userCoeffs.Add(new UserCoeff()
{
Coeff = coeff, UserId = u.Id
});
}
return(View(userCoeffs.OrderByDescending(c => c.Coeff).ToList()));
}
public IActionResult Hybrid(int id)
{
User user = _db.Users.FirstOrDefault(u => u.Id == id);
if (user == null)
{
return(NotFound());
}
List <User> users = _db.Users.Where(u => u.Id != id).ToList();
List <UserCoeff> userCoeffs = new List <UserCoeff>();
foreach (User u in users)
{
List <UserMark> usermarks1 = _db.UserMarks.Where(um => um.UserId == user.Id).ToList();
List <UserMark> usermarks2 = _db.UserMarks.Where(um => um.UserId == u.Id).ToList();
int lectionsNumber = _db.Lections.Count();
List <double> list1 = new double[lectionsNumber].ToList();
List <double> list2 = new double[lectionsNumber].ToList();
foreach (UserMark um in usermarks1)
{
list1[um.LectionId - 1] = um.Mark;
}
foreach (UserMark um in usermarks2)
{
list2[um.LectionId - 1] = um.Mark;
}
while (true)
{
int index1 = list1.IndexOf(0);
if (index1 != -1)
{
list1.RemoveAt(index1);
list2.RemoveAt(index1);
}
int index2 = list2.IndexOf(0);
if (index2 != -1)
{
list1.RemoveAt(index2);
list2.RemoveAt(index2);
}
if (index1 == -1 && index2 == -1)
{
break;
}
}
double coeff = CollaborationFilter.Correlation(list1.ToArray(), list2.ToArray());
userCoeffs.Add(new UserCoeff()
{
Coeff = coeff, UserId = u.Id
});
}
userCoeffs = userCoeffs.Take(5).OrderByDescending(u => u.Coeff).ToList();
List <double> reccomend = new double[_db.Lections.Count()].ToList();
foreach (UserCoeff uc in userCoeffs)
{
var userMarks = _db.UserMarks.Where(um => um.UserId == uc.UserId);
foreach (var mark in userMarks)
{
reccomend[mark.LectionId - 1] += mark.Mark * uc.Coeff;
}
}
double max = reccomend.Max();
List <HybridLectionCoeff> hlc = new List <HybridLectionCoeff>();
List <int> alreadyMarked = _db.UserMarks.Where(um => um.UserId == id).Select(um => um.LectionId).ToList();
List <int> dontShow = _db.UserLections.Where(um => um.UserId == id).Select(um => um.LectionId).ToList();
for (int i = 0; i < reccomend.Count; i++)
{
if (reccomend[i] > 0 && alreadyMarked.IndexOf(i + 1) == -1 && dontShow.IndexOf(i + 1) == -1)
{
hlc.Add(new HybridLectionCoeff()
{
LectionId = i + 1, Coeff = reccomend[i] / max, Source = "Collaboration"
});
}
}
List <UserMark> userMarksList = _db.UserMarks.Where(um => um.UserId == id).ToList();
List <Lection> lections = new List <Lection>();
foreach (UserMark um in userMarksList)
{
lections.Add(_db.Lections.FirstOrDefault(l => l.Id == um.LectionId));
}
if (lections.Count == 0)
{
return(View(new List <LectionCoeff>()));
}
double[,] coeffsMatrix = new double[_db.Lections.Count(), lections.Count];
List <Lection> allLections = _db.Lections.ToList();
allLections = allLections.Except(lections).ToList();
if (allLections.Count == 0)
{
return(View(new List <LectionCoeff>()));
}
int index = 0;
foreach (Lection l in lections)
{
foreach (Lection al in allLections)
{
coeffsMatrix[al.Id - 1, index] = Measures.CorrelationDistance(l, al) * Measures.EqualValues(l, al);
}
index++;
}
List <double> coeffsList = new double[allLections.Count].ToList();
for (int j = 0; j < allLections.Count; j++)
{
for (int i = 0; i < lections.Count; i++)
{
coeffsList[j] += coeffsMatrix[j, i];
}
}
max = coeffsList.Max();
for (int i = 0; i < coeffsList.Count; i++)
{
if (coeffsList[i] > 0)
{
if (hlc.FirstOrDefault(l => l.LectionId == i + 1) == null)
{
hlc.Add(new HybridLectionCoeff {
LectionId = i + 1, Coeff = coeffsList[i] / max, Source = "Content"
});
}
else
{
var lid = hlc.FirstOrDefault(l => l.LectionId == i + 1).LectionId;
for (int j = 0; j < hlc.Count; j++)
{
if (hlc[j].LectionId == lid)
{
hlc[j].Coeff += coeffsList[i] / max;
hlc[j].Source = "Hybrid";
}
}
}
}
}
List <int> dontshow = _db.UserLections.Where(ul => ul.UserId == id).Select(ul => ul.LectionId).ToList();
for (int i = 0; i < hlc.Count; i++)
{
if (dontshow.IndexOf(hlc[i].LectionId) != -1)
{
hlc.RemoveAt(i);
i--;
}
}
return(View(hlc.OrderByDescending(o => o.Coeff).ToList()));
}
public IActionResult Collaboration(int id)
{
User user = _db.Users.FirstOrDefault(u => u.Id == id);
if (user == null)
{
return(NotFound());
}
List <User> users = _db.Users.Where(u => u.Id != id).ToList();
List <UserCoeff> userCoeffs = new List <UserCoeff>();
foreach (User u in users)
{
List <UserMark> usermarks1 = _db.UserMarks.Where(um => um.UserId == user.Id).ToList();
List <UserMark> usermarks2 = _db.UserMarks.Where(um => um.UserId == u.Id).ToList();
int lectionsNumber = _db.Lections.Count();
List <double> list1 = new double[lectionsNumber].ToList();
List <double> list2 = new double[lectionsNumber].ToList();
foreach (UserMark um in usermarks1)
{
list1[um.LectionId - 1] = um.Mark;
}
foreach (UserMark um in usermarks2)
{
list2[um.LectionId - 1] = um.Mark;
}
while (true)
{
int index1 = list1.IndexOf(0);
if (index1 != -1)
{
list1.RemoveAt(index1);
list2.RemoveAt(index1);
}
int index2 = list2.IndexOf(0);
if (index2 != -1)
{
list1.RemoveAt(index2);
list2.RemoveAt(index2);
}
if (index1 == -1 && index2 == -1)
{
break;
}
}
double coeff = CollaborationFilter.Correlation(list1.ToArray(), list2.ToArray());
userCoeffs.Add(new UserCoeff()
{
Coeff = coeff, UserId = u.Id
});
}
userCoeffs = userCoeffs.Take(5).OrderByDescending(u => u.Coeff).ToList();
List <double> reccomend = new double[_db.Lections.Count()].ToList();
foreach (UserCoeff uc in userCoeffs)
{
var userMarks = _db.UserMarks.Where(um => um.UserId == uc.UserId);
foreach (var mark in userMarks)
{
reccomend[mark.LectionId - 1] += mark.Mark * uc.Coeff;
}
}
List <LectionCoeff> lc = new List <LectionCoeff>();
List <int> alreadyMarked = _db.UserMarks.Where(um => um.UserId == id).Select(um => um.LectionId).ToList();
List <int> dontShow = _db.UserLections.Where(um => um.UserId == id).Select(um => um.LectionId).ToList();
for (int i = 0; i < reccomend.Count; i++)
{
if (reccomend[i] > 0 && alreadyMarked.IndexOf(i + 1) == -1 && dontShow.IndexOf(i + 1) == -1)
{
lc.Add(new LectionCoeff()
{
Id = i + 1, Coeff = reccomend[i], UserId = id
});
}
}
return(View(lc.OrderByDescending(o => o.Coeff).ToList()));
}
