/// <summary>
/// 计算从源用户到目标用户的相似度
/// </summary>
/// <param name="user">目标用户</param>
/// <param name="srcClothesList">源用户衣物列表用户</param>
/// <returns>相似度值 范围为0-1 值越大相似度越高</returns>
private static double calculateUserSimilarity(User user, List <Clothes.Clothes> srcClothesList)
{
//获取匹配目标用户最近常穿的衣橱
IEnumerable <int> wardrobeIDs = WardrobeManager.getByUser(user.id).wardrobes.ToList().Select(x => x.id);
IEnumerable <IEnumerable <int> > clothesIDLists = wardrobeIDs.Select(x => ClothesManager.getByWardrobe(x).clothes.Select(y => y.id));
List <Clothes.Clothes> clothesList = new List <Clothes.Clothes>();
foreach (var clothesIDs in clothesIDLists)
{
foreach (var clothesID in clothesIDs)
{
clothesList.Add(ClothesManager.get(clothesID));
}
}
IEnumerable <Clothes.Clothes> mostDressedClothes = clothesList.OrderByDescending(x => x.wearingFrequency).OrderByDescending(x => x.lastWearingTime).Take(Config.matchClothesNum);
double ans = 0;
foreach (var clothes in mostDressedClothes)
{
double maxSimilarity = double.MinValue;
foreach (var targetClothes in srcClothesList)
{
double temp = ClothesManager.getSimilarity(new KeyValuePair <Clothes.Clothes, Clothes.Clothes>(targetClothes, clothes));
if (temp > maxSimilarity)
{
maxSimilarity = temp;
}
}
if (maxSimilarity > double.MinValue)
{
ans += maxSimilarity * Config.clothesTypeCoeffiencient[clothes.type];
}
}
if (mostDressedClothes.Any())
{
ans /= mostDressedClothes.Sum(x => Config.clothesTypeCoeffiencient[x.type]);
}
return(ans);
}
public ClothesResponseList getByWardrobe(int id)
{
return(ClothesManager.getByWardrobe(id));
}
/// <summary>
/// 查找与指定用户衣物喜好相似的用户
/// </summary>
/// <param name="id">源用户ID</param>
/// <returns>找到的所有相似用户ID列表</returns>
public static IEnumerable <User> similarUsers(string id)
{
User user = userDb.GetById(id);
if (user == null || WardrobeManager.getByUser(id).wardrobes.Count() == 0)
#if DEBUG
{ throw new Exception(); }
#else
{ return(new List <User>()); }
#endif
//获取源用户衣物列表
IEnumerable <int> wardrobeIDs = WardrobeManager.getByUser(user.id).wardrobes.ToList().Select(x => x.id);
IEnumerable <IEnumerable <int> > clothesIDLists = wardrobeIDs.Select(x => ClothesManager.getByWardrobe(x).clothes.Select(y => y.id));
List <Clothes.Clothes> clothes = new List <Clothes.Clothes>();
foreach (var clothesIDs in clothesIDLists)
{
foreach (var clothesID in clothesIDs)
{
clothes.Add(ClothesManager.get(clothesID));
}
}
Dictionary <double, User> similarUsers = new Dictionary <double, User>();
foreach (User anotherUser in userDb.GetList())
{
if (anotherUser.id == user.id)
{
continue;
}
double similarity = calculateUserSimilarity(anotherUser, clothes);
if (similarUsers.Count == 0 || similarity > similarUsers.Keys.Min())
{
if (similarUsers.Count == 0)
{
similarUsers.Add(similarity, anotherUser);
}
if (similarUsers.Count >= Config.matchUserNum)
{
similarUsers.Remove(similarUsers.Min().Key);
}
if (similarUsers.ContainsKey(similarity))
{
similarity += 0.000001;
}
similarUsers.Add(similarity, anotherUser);
}
}
return(similarUsers.Values);
}