Pandas, how to slice list made columns-CodePudding

Imagine, i have a column made by a bunch of of lists.

Column A 
List A of userids
List B of userids
List C of userids
List D of userids

And i want to acess list A, through index. Normally, i would just do

df['Column A'][0]

End result should be:

['ELEMENT OF LIST A', 'ELEMENT OF LIST A']

But i get a weird keyerror : 0. Any ideas on what i could do so i get that specific end result? I want to know that because i need to acess a list value according to the index of my loop.

As asked here is the dict output of a single row. It was the best i could do considering the size of the suceding ones.

{'Steps': {0: '1-Onboarding   Retorno'},
 'CampaignSource': {0: 'abd-ecomm-sms'},
 'UserId': {0: ['[email protected]',
   '[email protected]',
   '[email protected]']}}

CodePudding user response：

Assuming you have:

df = pd.DataFrame({'Column A': [['a', 'b', 'c'], ['d', 'e']]}, index=['i', 'j'])

#     Column A
# i  [a, b, c]
# j     [d, e]

Doing df['Column A'][0] would try to access the index 0 of the Series, which doesn't exist and raises a KeyError.

If you want to get all first items of the lists (as a Series) use:

df['Column A'].str[0]

output:

i    a
j    d
Name: Column A, dtype: object

To get the first element of the list at indices i/Column A:

df.loc['i', 'Column A'][0]
# 'a'

and for the first element of the first list of Column A:

df['Column A'].iloc[0][0]
# 'a'