我正在尝试获得一家餐厅的总星级评分的平均评分。顾客会评价这家餐厅。我制作了一个数据透视表来存储客户的评分。
import matplotlib.pyplot as plt title = [1,2,3,4] ititle = iter(title) fig, ax = plt.subplots(2, 2, figsize=(6, 8)) flat_ax = ax.flatten() for ax in flat_ax: ax.set_title(f'Title-{next(ititle)}')
The average rating =5
什么是公式,如何在php laravel中计算公式?
这是我的代码:
--------
place_ratings
---------------
user_id place_id rating
1 1 4
2 1 3
5 1 5
答案 0 :(得分:2)
请不要将所有place_ratings
条记录都删除掉,如果有成千上万的用户对餐厅进行评分,则会降低您的API速度。
尝试使用此查询:
PlaceRating::where('place_id',$id)->selectRaw('SUM(rating)/COUNT(user_id) AS avg_rating')->first()->avg_rating;
答案 1 :(得分:0)
这就是我的想法。我将其保留为一个集合,以利用集合方法:
public function placeRating($id)
{
$ratings = PlaceRating::where('place_id',$id)->get();
$ratingValues = [];
foreach ($rating as $aRating) {
$ratingValues[] = $aRating->rating;
}
$ratingAverage = collect($ratingValues)->sum() / $ratings->count();
return $ratingAverage;
}
答案 2 :(得分:0)
尝试一下。
使用$result = $sum/count($rateArray);
public function placeRating($id)
{
$rates = PlaceRating::where('place_id',$id)->select('rating')->get()->toArray();
$rateArray =[];
foreach ($rates as $rate)
{
$rateArray[]= $rate['rating'];
}
$sum = array_sum($rateArray);
$result = $sum/count($rateArray);
return response()->json(['rating'=>$result],200);
}