python - 处理可变列数数据框 - Python

Question

我正在尝试使用 Pandas 将列表列表写入 Excel 工作表 该列表如下所示:

List_of Lists = [ [1,2,3,4],
                  [5,6,7,8],
                  [9,10,11,12],
                  ........,
                ]

The number of these lists inside the main list could go up to a 1000. I also want to label them like colums1, colomns2, until colums100 for instance. on the same sheets. can anyone familiar with pandas help me? as this could be really easy for some?

Answer 1

我相信您可以将列表传递到 pd.DataFrame() 中，对于不存在的值，您只会得到 NaN。

例如:

List_of_Lists = [[1,2,3,4],
                 [5,6,7],
                 [9,10],
                 [11]]
df = pd.DataFrame(List_of_Lists)
print(df)
    0     1    2    3
0   1   2.0  3.0  4.0
1   5   6.0  7.0  NaN
2   9  10.0  NaN  NaN
3  11   NaN  NaN  NaN

然后以您想要的方式命名，只需使用 pandas.DataFrame.add_prefix

df = df.add_prefix('Column')
print(df)
   Column0  Column1  Column2  Column3
0        1      2.0      3.0      4.0
1        5      6.0      7.0      NaN
2        9     10.0      NaN      NaN
3       11      NaN      NaN      NaN

现在我想您可能还希望每个列表都是一列。在这种情况下，您需要转置您的 List_of_Lists。

from itertools import zip_longest

df = pd.DataFrame(list(map(list, zip_longest(*List_of_Lists))))
print(df)
   0    1     2     3
0  1  5.0   9.0  11.0
1  2  6.0  10.0   NaN
2  3  7.0   NaN   NaN
3  4  NaN   NaN   NaN