两个数据框之间的条件格式，在第二个DataFrame中，如果条件在第一个DataFrame中有效，我想说明为true

问题描述

import pandas as pd
rows = [] #create rows
offset=50
for i in range(0,1000,offset):  
     rows.append([i,"   "])
df = pd.DataFrame(rows,columns=["offset","Remark"]) # First data frame 

---

First Data Frame
      offset Remark
0        0       
1       50       
2      100       
3      150       
4      200       
5      250       
6      300       
7      350       
8      400       
9      450       
10     500       
11     550       
12     600       
13     650       
14     700       
15     750       
16     800       
17     850       
18     900       
19     950  

#  second data frame imported from excel,which is as below

   Start  End
0     50  100
1    300  400
2    450  600
3    800  950

期望的输出要求如下-在偏移列中“如果值在开始和结束之间或等于开始与结束之间，则注释列将被标记为True”

    offset       Remark
0        0       False  
1       50       True 
2      100       True 
3      150       False
4      200       False
5      250       False
6      300       True
7      350       True
8      400       True
9      450       True
10     500       True
11     550       True
12     600       True
13     650       False
14     700       False
15     750       False
16     800       True
17     850       True
18     900       True
19     950       True

解决方法

这是DataFrame.query的解决方案，

query = (
    " | ".join(f"{v['Start']} <= offset <= {v['End']}" 
               for _,v in df2[['Start','End']].iterrows())
)

# query: 50 <= offset <= 100 | 300 <= offset <= 400 | ...

---

index_ = df.query(query).index

df['Remark'] = False
df.loc[index_,'Remark'] = True

---

    offset  Remark
0        0   False
1       50    True
2      100    True
3      150   False
4      200   False
5      250   False
6      300    True
...