/// <summary>
/// gets list of criterionweights which the user should fill out
/// </summary>
/// <param name="issueId"></param>
/// <param name="userId">user who is performing the operation</param>
/// <returns></returns>
public static List <CriterionWeight> GetEmptyWeights(int issueId, int userId)
{
CriterionWeight cw;
ApplicationDBEntities ctx = new ApplicationDBEntities();
List <CriterionWeight> list = new List <CriterionWeight>();
var query = from Criterion in ctx.Criterion
where
Criterion.Issue == issueId
select new
{
Id = Criterion.Id,
Name = Criterion.Name,
Description = Criterion.Description,
Issue = Criterion.Issue,
Weight = Criterion.Weight,
WeightPC = Criterion.WeightPC
};
foreach (var c in query.AsNoTracking())
{
cw = new CriterionWeight();
cw.CriterionId = c.Id;
cw.UserId = userId;
cw.Weight = 0.0;
list.Add(cw);
}
ctx.Dispose();
return(list);
}
/// <summary>
/// returns all criterionweights of an Issue
/// </summary>
/// <param name="issueId"></param>
/// <param name="userId">user who is performing this operation</param>
/// <returns></returns>
public static List <CriterionWeight> GetIssueWeights(int issueId, int userId)
{
List <CriterionWeight> list = new List <CriterionWeight>();
CriterionWeight cw;
ApplicationDBEntities ctx = new ApplicationDBEntities();
var query = from CriterionWeight in ctx.CriterionWeight
where
(from Criterion in ctx.Criterion
where
Criterion.Issue == issueId
select new
{
Criterion.Id
}).Contains(new { Id = CriterionWeight.CriterionId })
select new
{
UserId = CriterionWeight.UserId,
CriterionId = CriterionWeight.CriterionId,
Weight = CriterionWeight.Weight
};
foreach (var c in query.AsNoTracking())
{
cw = new CriterionWeight();
cw.CriterionId = c.CriterionId;
cw.Weight = c.Weight;
cw.UserId = c.UserId;
list.Add(cw);
}
ctx.Dispose();
return(list);
}
/// <summary>
/// tries to save criteria weight comparisons
/// </summary>
/// <param name="list">list of comparisons to be saved</param>
/// <returns>returns true if consistency check OK and save is performed
/// if consistency check faild returns false</returns>
public static List <CriterionWeight> SaveWeightComparison(List <PairwiseComparisonCC> list)
{
List <CriterionWeight> criteriaWeights = new List <CriterionWeight>();
if (list == null || list.Count == 0)
{
return(criteriaWeights);
}
//first check if user has made comparisons
//if true then delete old comparisons
ApplicationDBEntities ctx = new ApplicationDBEntities();
int issueId = ctx.Criterion.Find(list[0].CriterionLeft).Issue;
int userId = list[0].UserId;
string sqlQuery = "SELECT COUNT(*) FROM PairwiseComparisonCC WHERE UserId = {0} AND CriterionLeft IN (SELECT Id From Criterion Where Issue = {1})";
if (ctx.Database.SqlQuery <int>(sqlQuery, userId, issueId).FirstOrDefault() > 0)
{
sqlQuery = "DELETE FROM PairwiseComparisonCC WHERE UserId = {0} AND CriterionLeft IN (SELECT Id From Criterion Where Issue = {1})";
ctx.Database.ExecuteSqlCommand(sqlQuery, userId, issueId);
sqlQuery = "DELETE FROM CriterionWeight WHERE UserId = {0} AND CriterionId IN (SELECT Id From Criterion Where Issue = {1})";
ctx.Database.ExecuteSqlCommand(sqlQuery, userId, issueId);
ctx.SaveChanges();
}
sqlQuery = "SELECT Count(*) From Criterion Where Issue = {0}";
int critCnt = ctx.Database.SqlQuery <int>(sqlQuery, issueId).FirstOrDefault();
//sort comparisons
list = list.OrderBy(x => x.CriterionLeft).ThenBy(x => x.CriterionRight).ToList();
//create reciprocal matrix
Matrix <double> critMatrix = Matrix <double> .Build.Dense(critCnt, critCnt, 1.0);
int i = 0;
int j = 1;
foreach (var pcc in list)
{
if (j == critCnt)
{
i++;
j = i + 1;
}
critMatrix[i, j] = pcc.Value;
critMatrix[j, i] = 1.0 / pcc.Value;
j++;
}
//if consistency check ok insert criterion weights
if (AhpConsistency(critMatrix))
{
foreach (var pcc in list)
{
ctx.PairwiseComparisonCC.Add(pcc);
ctx.Entry(pcc).State = System.Data.Entity.EntityState.Added;
}
ctx.SaveChanges();
Vector <double> priorityWeightVector = Eigenvector(critMatrix);
List <Criterion> cList = ctx.Criterion.Where(x => x.Issue == issueId).OrderBy(x => x.Id).ToList();
CriterionWeight cw;
i = 0;
foreach (Criterion c in cList)
{
cw = new CriterionWeight();
cw.UserId = userId;
cw.CriterionId = c.Id;
cw.Weight = priorityWeightVector[i];
ctx.CriterionWeight.Add(cw);
ctx.Entry(cw).State = System.Data.Entity.EntityState.Added;
criteriaWeights.Add(cw);
i++;
}
ctx.SaveChanges();
ctx.Dispose();
}
return(criteriaWeights);
}
