您需要从：

$中删除（） b
$ b

  df ['Monday'] =（df.index.get_level_values（0）.weekday == 0）.astype（int）

打印（df）
访客星期一
日期时间
 2017-09-11 4:45 0 1 
 5:00 1 1 
 5:15 26 1 
 2017-09-12 4:45 0 0 
 5:00 1 0 
 5:15 26 0 
 

---

 名称= [['Monday'，'Tuesday'，'Wednesday'，'Thursday'，'Friday'，'Saturday'，'Sunday'] 

 for i，x inumerate（names）：
 df [x] =（df.index.get_level_values（0）.weekday == i）.astype（int）
打印（df）
访客星期一星期二星期三星期四星期五\ 
日期时间
 2017-09-11 4:45 0 1 0 0 0 0 
 5:00 1 1 0 0 0 0 
 5:15 26 1 0 0 0 0 
 2017-09-12 4:45 0 0 1 0 0 0 
 5:00 1 0 1 0 0 0 
 5:15 26 0 1 0 0 0 

星期六星期日
日期时间
 2017-09-11 4:45 0 0 
 5:00 0 0 
 5:15 0 0 
 2017-09-12 4:45 0 0 
 5:00 0 0 
 5:15 0 0 
 

另一个解决方案是改进的另一个原始答案-需要 DatetimeIndex.weekday_name 和 get_dummies ，然后是 set_index ，如果原始索引对于添加missig名称，必须添加reindex：

  names = ['Monday'，'Tuesday' ，星期三，星期四，星期五，星期六，星期日] 

 df1 = df.join（pd.get_dummies（df.index.get_level_values（0）.weekday_name） 
 .set_index（df.index）.reindex（columns = names，fill_value = 0））
打印（df1）
访客星期一星期二星期三星期四星期五\ 
日期时间
 2017-09-11 4:45 0 1 0 0 0 0 
 5:00 1 1 0 0 0 0 
 5:15 26 1 0 0 0 0 
 2017-09 -12 4:45 0 0 1 0 0 0 
 5:00 1 0 1 0 0 0 
 5:15 26 0 1 0 0 0 

星期六星期日
日期时间
 2017-09-11 4:45 0 0 
 5:00 0 0 
 5:15 0 0 
 2017-09-12 4:45 0 0 
 5:00 0 0 
 5:15 0 0 
 

I have a dataframe with a double index (day, time) and would like to create new columns 'Monday', 'Tuesday', 'Wednesday' etc equal to one if the index day is in the correct day.

My original dataframe:

                       Visitor  
Date       Time                                                              
2017-09-11 4:45           0         
           5:00           1        
           5:15          26       
....
2017-09-12 4:45           0       
           5:00           1         
           5:15          26     
....

What I would like to have:

                       Visitor      Monday    Tuesday
Date       Time                                                              
2017-09-11 4:45           0           1          0
           5:00           1           1          0
           5:15          26           1          0
....
2017-09-12 4:45           0           0          1
           5:00           1           0          1
           5:15          26           0          1
....

Here is what I tried:

df['Monday'] = (df.index.get_level_values(0).weekday() == 0)

However I get an error saying "'Int64Index' object is not callable".

Thanks in advance!

You need remove () from :

df['Monday'] = (df.index.get_level_values(0).weekday == 0).astype(int)

print (df)
                 Visitor  Monday
Date       Time                 
2017-09-11 4:45        0       1
           5:00        1       1
           5:15       26       1
2017-09-12 4:45        0       0
           5:00        1       0
           5:15       26       0

---

names = ['Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday', 'Sunday']

for i, x in enumerate(names):
    df[x] = (df.index.get_level_values(0).weekday == i).astype(int)
print (df)
                 Visitor  Monday  Tuesday  Wednesday  Thursday  Friday  \
Date       Time                                                          
2017-09-11 4:45        0       1        0          0         0       0   
           5:00        1       1        0          0         0       0   
           5:15       26       1        0          0         0       0   
2017-09-12 4:45        0       0        1          0         0       0   
           5:00        1       0        1          0         0       0   
           5:15       26       0        1          0         0       0   

                 Saturday  Sunday  
Date       Time                    
2017-09-11 4:45         0       0  
           5:00         0       0  
           5:15         0       0  
2017-09-12 4:45         0       0  
           5:00         0       0  
           5:15         0       0  

Another solution is a improved another original answer - need DatetimeIndex.weekday_name with get_dummies, then set_index by original index and if necessary add reindex for add missig names:

names = ['Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday', 'Sunday']

df1 = df.join(pd.get_dummies(df.index.get_level_values(0).weekday_name)
                .set_index(df.index).reindex(columns=names, fill_value=0))
print (df1)
                 Visitor  Monday  Tuesday  Wednesday  Thursday  Friday  \
Date       Time                                                          
2017-09-11 4:45        0       1        0          0         0       0   
           5:00        1       1        0          0         0       0   
           5:15       26       1        0          0         0       0   
2017-09-12 4:45        0       0        1          0         0       0   
           5:00        1       0        1          0         0       0   
           5:15       26       0        1          0         0       0   

                 Saturday  Sunday  
Date       Time                    
2017-09-11 4:45         0       0  
           5:00         0       0  
           5:15         0       0  
2017-09-12 4:45         0       0  
           5:00         0       0  
           5:15         0       0