list - Pandas 从列表列表中一次添加多个新列

Question

我有一个时间戳列表列表，其中每个内部列表如下所示:
['Tue', 'Feb', '7', '10:07:40', '2017']
Pandas 是否可以同时将五个新列添加到已经创建的数据帧(与外部列表长度相同)，这些列等于这些值中的每一个，名称为 'day','month','date','time','year' ?

Answer 1

我想你可以用 DataFrame构造函数 concat :

df = pd.DataFrame({'A':[1,2,3],
                   'B':[4,5,6],
                   'C':[7,8,9]})

L = [['Tue', 'Feb', '7', '10:07:40', '2017'],
     ['Tue', 'Feb', '7', '10:07:40', '2017'],
     ['Tue', 'Feb', '7', '10:07:40', '2017']]

cols = ['day','month','date','time','year']
df1 = pd.DataFrame(L, columns=cols)
print (df1)
   day month date      time  year
0  Tue   Feb    7  10:07:40  2017
1  Tue   Feb    7  10:07:40  2017
2  Tue   Feb    7  10:07:40  2017

df2 = pd.concat([df, df1], axis=1)
print (df2)
   A  B  C  day month date      time  year
0  1  4  7  Tue   Feb    7  10:07:40  2017
1  2  5  8  Tue   Feb    7  10:07:40  2017
2  3  6  9  Tue   Feb    7  10:07:40  2017

一个类轮:

df2 = pd.concat([df, pd.DataFrame(L, columns=['day','month','date','time','year'])], axis=1)
print (df2)
   A  B  C  day month date      time  year
0  1  4  7  Tue   Feb    7  10:07:40  2017
1  2  5  8  Tue   Feb    7  10:07:40  2017
2  3  6  9  Tue   Feb    7  10:07:40  2017