通过客户ID查找两个产品之间的时间

Question

我需要找到一个客户已经买了P1，多少天后客户会买P2。我无法找到同一客户从订购P1到下一次订购P2之间的天数。

我的数据如下图所示，我需要找到一个客户已经购买了P1，并且在多少天后客户会购买P2。

Customer ID Order_Date Product
C-87 11/20/2018 P2
C-87 7/25/2018 P1
C-87 7/19/2019 P1
C-87 8/2/2018 P2
C-87 12/9/2019 P1
... ... ... ... ... 
C-22 9/22/2018 P2
C-22 9/4/2018 P2
C-22 1/15/2018 P1
C-22 9/5/2019 P2
C-22 3/20/2018 P1 12

Answer 1

试试这个。

df['Order_Date'] = pd.to_datetime(df['Order_Date'])
df.sort_values(['ID', 'Order_Date', 'Product'], inplace = True)

df['next_order_date'] = df['Order_Date'].shift(-1)
df['next_product'] = df['Product'].shift(-1)

df['days'] = df.apply(lambda row: row['next_order_date'] - row['Order_Date'] if ((row['next_product'] == 'P2') & (row['Product'] == 'P1')) else np.nan, axis = 1)

结果在

    ID  Order_Date  Product next_oder_date  days
7   C-22    2018-01-15  P1  2018-09-04  232 days
6   C-22    2018-09-04  P2  2018-09-22  NaT
5   C-22    2018-09-22  P2  2019-09-05  NaT
8   C-22    2019-09-05  P2  2018-07-25  NaT
1   C-87    2018-07-25  P1  2018-08-02  8 days
3   C-87    2018-08-02  P2  2018-11-20  NaT
0   C-87    2018-11-20  P2  2019-07-19  NaT
2   C-87    2019-07-19  P1  2019-12-09  143 days
4   C-87    2019-12-09  P1  NaT         NaT