CODEWITHSUNDEEP
pythonpandaslistdataframe
AdrixnIPP
AdrixnIPP

Reputation: 31

How to create lists based on index or the A column in a dataframe?

I have this dataframe :

 A     B      C
 1     14    100
 1     15    101
 1     16    102
 2     17    103
 2     18    104
 3     19    105
 3     20    106
...   ...    ...
 n

and I would like this output for any number up to n for the whole dataframe :

l1 = [14, 15, 16] (the 1 in A column)
l2 = [17,18]  (the 2 in A column)
l3 = [19,20] (the 3 in A column)

Could you please help me? Tanks !

Upvotes: 0

Views: 188

Answers (1)

fishmulch
fishmulch

Reputation: 376

Try:

l1, l2, l3 = df.groupby('A')['B'].apply(list).values

Unpacking will only work only if there are three unique values in df['A'], so you probably wouldn't want to unpack the values and just index the resulting DataFrame from:

>>> df.groupby('A')['B'].apply(list)
A
1    [14, 15, 16]
2        [17, 18]
3        [19, 20]

Upvotes: 5

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