public async Task <bool> CalculateAlternativeWeights(Guid choiceId, double[] choiceWeights, List <ICriterionModel> criteria)
{
var alternatives = await _alternativeRepository.GetByChoiceIDAsync(choiceId);
var hash = new Dictionary <Guid, int>();
int i = 0;
foreach (var alternative in alternatives)
{
hash[alternative.AlternativeID] = i;
i++;
}
var weights = new List <double[]>();
foreach (var criterion in criteria)
{
double[,] matrix = new double[alternatives.Count, alternatives.Count];
foreach (var alternative in alternatives)
{
matrix[hash[alternative.AlternativeID], hash[alternative.AlternativeID]] = 1;
var comparisons = await _alternativeComparisonRepo.GetByCriteriaAndFirstAlternativeIDAsync(criterion.CriteriaID, alternative.AlternativeID);
foreach (var comparison in comparisons)
{
matrix[hash[comparison.AlternativeID1], hash[comparison.AlternativeID2]] = comparison.AlternativeRatio;
matrix[hash[comparison.AlternativeID2], hash[comparison.AlternativeID1]] = 1 / comparison.AlternativeRatio;
}
}
var weight = _AHPService.CalculatePriortyVector(matrix);
var consistency = _AHPService.CalculateConsistency(matrix, weight);
if (consistency > 0.1)
{
foreach (var alternative in alternatives)
{
var comparisons = await _alternativeComparisonRepo.GetByCriteriaAndFirstAlternativeIDAsync(criterion.CriteriaID, alternative.AlternativeID);
foreach (var comparison in comparisons)
{
comparison.AlternativeRatio = 0;
await _alternativeComparisonRepo.UpdateAsync(comparison);
}
}
await _alternativeComparisonRepo.SaveAsync();
return(false);
}
weights.Add(weight);
}
double[,] alternativeWeightMatrix = new double[alternatives.Count, criteria.Count];
i = 0;
foreach (var weight in weights)
{
for (int j = 0; j < alternatives.Count; j++)
{
alternativeWeightMatrix[j, i] = weight[j];
}
i++;
}
var alternativeScores = _AHPService.FinalCalculate(choiceWeights, alternativeWeightMatrix);
//sprema dobivene scoreove
using (var uof = _unitOfWorkFactory.Create())
{
i = 0;
foreach (var alternative in alternatives)
{
alternative.AlternativeScore = alternativeScores[i];
await _alternativeRepository.UpdateAsync(alternative);
i++;
}
await _alternativeRepository.SaveAsync();
uof.Commit();
}
return(true);
}
