Squish multiple rows in multiple columns into one row in Pandas

Question

I need to squish multiple rows into one row across multiple columns in pandas.

For example,

df = pd.DataFrame({'A':[1,2,1,1,2,3], 'B':['b1','b2','b3','b4','b5','b6'], 'C':['c','c','c','c','c','c'], 'D':['d1','d2','d3','d4','d5','d6']})

print(df)
   A   B  C   D
0  1  b1  c  d1
1  2  b2  c  d2
2  1  b3  c  d3
3  1  b4  c  d4
4  2  b5  c  d5
5  3  b6  c  d6

here 'A' is the identifier to be used as reference for grouping rest of the rows across the columns and I'd like to convert the dataframe into the following format,

print(df)
   A   B        C   D
0  1  b1,b3,b4  c  d1,d3,d4
1  2  b2,b5     c  d2,d5
2  3  b6        c  d3

score 2 · Accepted Answer · answered Sep 25 '19 at 19:18

2

With groupby

df.groupby(['A', 'C'], as_index=False).agg(','.join)

answered Sep 25 '19 at 19:18

phi

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Why is this returning an Empty Dataframe? – scrollout Nov 17 '22 at 15:15

Squish multiple rows in multiple columns into one row in Pandas

1 Answers1