python：如何对包含字符串数组的列进行热编码

我想知道如何对包含字符串数组的列进行热编码

我正在尝试从df到df2：

import pandas as pd

# This is the original data frame
df = pd.DataFrame({'menu': [['Italian', 'Greek'], ['Japanese'],
                   ['Italian','Greek', 'Japanese']], 'price': ['$$', '$$', '$']})

df.head()

# This is the desired result

df2 = pd.DataFrame({'menu': [['Italian', 'Greek'], ['Japanese'], 
['Italian','Greek', 'Japanese']], 
                    'price': ['$$', '$$', '$'], 
                    'Italian': [1,0,1],
                    'Greek': [1,0,1],
                    'Japanese': [0,1,1]
                   })
df2.head()

用于：

---

您可以使用

pd.get_dummies

，

pd.apply

，

DataFrame.join

和

Series.stack

df.join(pd.get_dummies(df.menu.apply(pd.Series).stack()).sum(level=0))

输出：

                         menu price  Greek  Italian  Japanese
0            [Italian, Greek]    $$      1        1         0
1                  [Japanese]    $$      0        0         1
2  [Italian, Greek, Japanese]     $      1        1         1

                         menu price  Greek  Italian  Japanese
0            [Italian, Greek]    $$      1        1         0
1                  [Japanese]    $$      0        0         1
2  [Italian, Greek, Japanese]     $      1        1         1