python - 我如何以这样的方式分割 pandas 数据框，为每个分割值创建一个列

Question

例如。

输入数据框

Name     Subjects
Ramesh   Maths,Science
Rakesh   MAths,Science,Social Studies
John     Social Science, Lietrature

输出数据框

Name     Subject1       Subject2     Subjects3
Ramesh   Maths          Science      NaN
Rakesh   MAths          Science      Social Studies
John     Social Science Literature   Nan

Answer 1

您可以根据 str.split 的结果创建一个新的 df然后concat他们:

In [66]:
subjects = df['Subjects'].str.split(',', expand=True)
subjects

Out[66]:
                0           1               2
0           Maths     Science            None
1           MAths     Science  Social Studies
2  Social Science  Lietrature            None

In [71]:    
subjects.columns = ['Subject ' + str(x + 1) for x in range(len(subjects.columns))]
subjects

Out[71]:
        Subject 1   Subject 2       Subject 3
0           Maths     Science            None
1           MAths     Science  Social Studies
2  Social Science  Lietrature            None

In [74]:
concatenated = pd.concat([df,subjects], axis=1)
concatenated.drop('Subjects',axis=1,inplace=True)
concatenated

Out[74]:
     Name       Subject 1   Subject 2       Subject 3
0  Ramesh           Maths     Science            None
1  Rakesh           MAths     Science  Social Studies
2    John  Social Science  Lietrature            None