public override void Recommend()
{
SignedBeliefPropagation BP = new SignedBeliefPropagation(edge_list, node_potential_like, node_potential_dislike,
propagation_matrix_like, propagation_matrix_dislike, max_user_id, max_item_id);
recommend_user_item = new Dictionary <int, List <Score> >();
int num = 0;
foreach (int target_user in correct_user_item.Keys)
{
if (!node_potential_like.ContainsKey(target_user))
{
continue;
}
if (num != 0)
{
edge_list.Clear();
}
List <Score> recommend_items = new List <Score>();
recommend_items = PerformBP(BP, target_user, num);
recommend_user_item.Add(target_user, recommend_items);
num++;
if (num % 50 == 0)
{
Console.WriteLine("Compute BP score for {0} user / {1} users (fold{2}): Complete", num, correct_user_item.Count(), fold);
}
}
Console.WriteLine("Compute BP scores: Complete");
}
public List <Score> PerformBP(SignedBeliefPropagation BP, int target_user, int num)
{
List <Score> belief_score_list = new List <Score>();
BP.AssignNodePotential(target_user);
for (int iter = 0; iter < num_iter; iter++)
{
// message passing
BP.PassMessage(target_user, iter);
belief_score_list = BP.ComputeBeliefScore(target_user, test_items, num_recommend, correct_user_item);
}
List <Score> recommend_items = new List <Score>();
foreach (Score items in belief_score_list)
{
if (candidate_item == "Longtail_items")
{
if (Program.tophead_items.Contains(items.item_id))
{
continue;
}
}
if (node_potential_like[target_user].linkednode_list.Contains(items.item_id))
{
continue;
}
//if (node_potential_dislike.ContainsKey(target_user))
// if (node_potential_dislike[target_user].linkednode_list.Contains(items.item_id)) continue;
if (recommend_items.Count < num_recommend)
{
Score user_score = new Score(items.item_id, items.score);
recommend_items.Add(user_score);
}
else
{
break;
}
}
// 메모리 부족으로 이미 BP 수행한 target user 관련 데이터 지움
node_potential_like.Remove(target_user);
BP.Clean(target_user);
return(recommend_items);
}