python - 按日期和城市重新采样和聚合数据框

Question

我想按日期重新采样数据框并根据城市 df 的总和创建一列：

+-----------------+-------------------+------------+
| booking_date    |  Cities           |  province  | 
+-----------------+-------------------+------------+
|  15-12-17       |  Kota Depok       | Jawa Barat |    
|  15-12-17       |  Bogor            | Jawa Barat |      
|  15-12-17       |  Kota Depok       | Jawa Barat |     
|  15-12-17       |  Kota Bandung     | Jawa Barat |    
|  15-12-17       |  Kota Bandung     | Jawa Barat |   
+-----------------+-------------------+------------+

输出可能如下所示：

df:

+-----------------+-------------------+------------+------------+
| booking_date    |  Cities           |  province  |  Count     | 
+-----------------+-------------------+------------+------------+
|  15-12-17       |  Kota Depok       | Jawa Barat |  2         |
|  15-12-17       |  Bogor            | Jawa Barat |  1         |
|  15-12-17       |  Kota Bandung     | Jawa Barat |  2         | 
+-----------------+-------------------+------------+------------+

如何实现？

标签： pythonpandasdataframe

Answer 1

GroupBy.size与Series.reset_index和name参数一起使用：

df = df.groupby(['booking_date','Cities','province']).size().reset_index(name='Count')