python - Pandas-合并两列(一列是列表，一列是字符串)

Question

想要合并两列，一列是字符串，另一列是字符串列表，想要将字符串追加到另一列的列表中，例如:

input: 
A   B    
5 [1,2]
2 [3,4]

return:
A  B     C
5 [1,2]  [1,2,5]
2 [3,4]  [3,4,2]

尝试使用 apply 但不知道如何处理不同类型的列

Answer 1

使用DataFrame.apply:

>>> df = pd.DataFrame({'A': ['5', '2'], 'B': [[1, 2], [3, 4]]})
>>> df['C'] = df.apply(lambda r: r['B'] + [r['A']], axis=1)
>>> df
   A       B          C
0  5  [1, 2]  [1, 2, 5]
1  2  [3, 4]  [3, 4, 2]

---

>>> df['C'] = df['B'] + df['A'].apply(lambda x: [x])
>>> df
   A       B          C
0  5  [1, 2]  [1, 2, 5]
1  2  [3, 4]  [3, 4, 2]