Python 从一列中添加或派生两列

给定以下数据帧：

-

如何在上述数据框中再添加两列

大宗报价

例如，第1列有“是”答案的计数，第2列有“否”答案的计数

 -+------------------+--------------------++--------------------+
|Customer_ID|Project_ID|QUESTION_TYP|ANSWER|col_1|col_2
+---------+----------+-------------+---------+------+-------------
   1            1         2nd QUES      YES.    2     0
   1            2          2nd QUES     NO      0.    1
   1            2          2nd Ques.    Yes     1.    0

---

请帮忙。我已经尝试了大多数解决方案，但得到的结果是肯定或否定，但我希望按行。请帮助这看起来像窗口函数。假设您希望通过

客户id

进行计数：

select t.*,
       sum(case when answer = 'YES' then 1 else 0 end) over (partition by customer_id) as col_1,
       sum(case when answer = 'NO' then 1 else 0 end) over (partition by customer_id) as col_2
from t;

或者，如果您想对所有数据进行计数，只需将

（按客户id划分）

替换为

（）

注意：这会将计数放在两列中。如果只希望列中的计数与行中的答案匹配：

select t.*,
       (case when answer = 'YES'
             then sum(case when answer = 'YES' then 1 else 0 end) over (partition by customer_id)
             else 0
        end) as col_1,
       (case when answer = 'NO'
             then sum(case when answer = 'NO' then 1 else 0 end) over (partition by customer_id)
             else 0
        end) as col_2
from t;

---

然而，我认为这两项都有意义。

您尝试过什么？

select t.*,
       (case when answer = 'YES'
             then sum(case when answer = 'YES' then 1 else 0 end) over (partition by customer_id)
             else 0
        end) as col_1,
       (case when answer = 'NO'
             then sum(case when answer = 'NO' then 1 else 0 end) over (partition by customer_id)
             else 0
        end) as col_2
from t;