在python django中列出超出范围的索引

如何解决在python django中列出超出范围的索引

我在 django 中使用 python 创建了一个书籍推荐应用程序，所以我试图应用机器学习的 k 均值算法，但是当我运行它时，我在 /log_in/ 列表索引超出范围时出现 IndexError “在最后一行代码中”，这是代码：

  # Save session as cookie to login the user
        login(request,user)
      # get request user reviewed books
        user_reviews = BxBookratings.objects.filter(id=request.user.id)
        user_reviews_books_ids = set(map(lambda x: x.isbn,user_reviews))     
     #create matrix
        all_user_names = map(lambda x: x.username,BxUsers.objects.only("username"))
        all_books_ids = set(map(lambda x: x.books_id,BxBooks.objects.only("books_id")))
        num_users = len(list(all_user_names))

        ratings_m = dok_matrix((num_users,max(all_books_ids)+1),dtype=np.float32)
        all_user_names1= list(all_user_names)
       
        for i in all_user_names: # each user corresponds to a row,in the order of all_user_names
    
            user_reviews = BxUsers.objects.filter(username= all_user_names1[i])
            for user_review in user_reviews:
              ratings_m[i,user_review.books_id] = user_review.book_rating
        # Perform kmeans clustering
      #  k = int(num_users / 10) + 2
        k=4
        kmeans = KMeans(n_clusters=k)
        clustering = kmeans.fit(ratings_m.tocsr())
          
        Cluster.objects.all().delete()
        new_clusters = {i: Cluster(name=i) for i in range(k) }
        for cluster in new_clusters.values(): # clusters need to be saved before referring to users
              cluster.save()
        for i,cluster_label in enumerate(clustering.labels_):  
              new_clusters[cluster_label].users.add(BxUsers.objects.get(username=all_user_names1[i]))

谢谢你帮我解决这个问题