写一段实现Django房源协同过滤推荐的代码
时间: 2024-01-02 19:44:28 浏览: 78
好的,我可以为您写一段实现Django房源协同过滤推荐的代码:
```python
# 引入必要的库和模块
from django.shortcuts import render
from django.http import HttpResponse
from .models import House, User, Rating
import numpy as np
from sklearn.metrics.pairwise import cosine_similarity
# 实现协同过滤推荐
def collab_filtering(user_id):
# 获取用户评分数据
users_ratings = Rating.objects.filter(user=user_id)
# 获取所有用户的评分数据
all_ratings = Rating.objects.all()
# 创建一个矩阵来存储所有用户的评分数据
user_rating_matrix = np.zeros((len(User.objects.all()), len(House.objects.all())))
# 将用户评分数据加入到矩阵中
for rating in users_ratings:
user_rating_matrix[rating.user.id - 1][rating.house.id - 1] = rating.rating
# 计算余弦相似性矩阵
similarity_matrix = cosine_similarity(user_rating_matrix)
# 获取与当前用户最相似的用户
sim_users = np.argsort(similarity_matrix[user_id-1])[::-1][:5]
# 从相似用户中获取已评价过的房源列表
sim_users_ratings = Rating.objects.filter(user__in=sim_users).exclude(user=user_id)
# 统计每个房源的平均评分
avg_ratings = {}
for house in House.objects.all():
avg_ratings[house.id] = np.mean(Rating.objects.filter(house=house).values_list('rating', flat=True))
# 计算每个房源的预测评分
predictions = {}
for house in House.objects.all():
if not Rating.objects.filter(user=user_id, house=house).exists():
numerator = 0
denominator = 0
for rating in sim_users_ratings.filter(house=house):
similarity = similarity_matrix[user_id-1][rating.user.id-1]
numerator += similarity * (rating.rating - avg_ratings[rating.house_id])
denominator += np.abs(similarity)
if denominator != 0:
predictions[house] = avg_ratings[house.id] + (numerator / denominator)
else:
predictions[house] = avg_ratings[house.id]
# 获取预测评分最高的10个房源
recommended_houses = sorted(predictions.items(), key=lambda x: x[1], reverse=True)[:10]
return recommended_houses
# 创建一个视图函数用于展示推荐结果
def recommend(request):
# 获取请求中的当前用户ID
user_id = request.GET.get('user_id')
# 调用协同过滤推荐函数获取推荐结果
recommended_houses = collab_filtering(int(user_id))
# 将结果渲染到页面中
context = {'user_id': user_id, 'recommended_houses': recommended_houses}
return render(request, 'recommend.html', context)
```
以上是一个简单的Django房源协同过滤推荐的代码实现,仅供参考。
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