簡單的旋轉

首先嚐試使用 pivot ：

import pandas as pd
import numpy as np

df = pd.DataFrame({'Name':['Mary', 'Josh','Jon','Lucy', 'Jane', 'Sue'],
                   'Age':[34, 37, 29, 40, 29, 31],
                   'City':['Boston','New York', 'Chicago', 'Los Angeles', 'Chicago', 'Boston'],
                   'Position':['Manager','Programmer','Manager','Manager','Programmer', 'Programmer']},
                    columns=['Name','Position','City','Age'])

print (df)
   Name    Position         City  Age
0  Mary     Manager       Boston   34
1  Josh  Programmer     New York   37
2   Jon     Manager      Chicago   29
3  Lucy     Manager  Los Angeles   40
4  Jane  Programmer      Chicago   29
5   Sue  Programmer       Boston   31

print (df.pivot(index='Position', columns='City', values='Age'))
City        Boston  Chicago  Los Angeles  New York
Position                                          
Manager       34.0     29.0         40.0       NaN
Programmer    31.0     29.0          NaN      37.0

如果需要重置索引，請刪除列名稱並填充 NaN 值：

#pivoting by numbers - column Age
print (df.pivot(index='Position', columns='City', values='Age')
         .reset_index()
         .rename_axis(None, axis=1)
         .fillna(0))
         
     Position  Boston  Chicago  Los Angeles  New York
0     Manager    34.0     29.0         40.0       0.0
1  Programmer    31.0     29.0          0.0      37.0

#pivoting by strings - column Name
print (df.pivot(index='Position', columns='City', values='Name'))   
      
City       Boston Chicago Los Angeles New York
Position                                      
Manager      Mary     Jon        Lucy     None
Programmer    Sue    Jane        None     Josh