Pandas：以元组长度1解压缩列

Question

I have a DataFrame df with many column values like so:

index   Column1
0       [data1]
1       [data2]
2       [data3]
3       [data4]
4       [data5]
5       [data6]

I am looking for a simple Pandas or NumPy command to convert it to a DataFrame like this:

index   Column1
0       data1
1       data2
2       data3
3       data4
4       data5
5       data6

Currently I am doing:

df[Column1] = [each[0] for each in df[Column1]]

but this would require me to loop through all the columns.

Answer 1

You can use the str accessor to get the element out of the list:

df['Column1'] = df['Column1'].str[0]

For instance:

>>> df
   Column1
0  [item1]
1  [item2]
2  [item3]

>>> df['Column1'].str[0]
0    item1
1    item2
2    item3

The primary use of str is to open up a column or Series to Pandas' vectorised string operations, but it can also be useful if the values in the column are Python lists.