How can I duplicate a value or string in pandas?

Question

I have the a pandas columns containing multiple strings. I want all these strings to be duplicated 3 times.

df = pd.DataFrame(data = ['a','b','c']),

Desired output:

I want to transform this table so it looks like this:

I can't seem to find an easy way to do this.

Anything will help.

Does this answer your question? [How to repeat Pandas data frame?](https://stackoverflow.com/a/23887956/13552470) — Red, Jul 25 '20 at 19:15

score 4 · Answer 1 · answered Jul 25 '20 at 19:10

4

Try:

df[0].repeat(3).reset_index(drop=True)

Out:

0    a
1    a
2    a
3    b
4    b
5    b
6    c
7    c
8    c
Name: 0, dtype: object

answered Jul 25 '20 at 19:10

Mark Moretto

`pd.concat([df]*3).sort_values(0)` – Herwini Jul 25 '20 at 21:24
I mean, OP had a unique index. `pd.concat([df]*3).sort_values(0)` gives me `[0,0,0,1,1,1,2,2,2,]`. – Mark Moretto Jul 25 '20 at 21:55

score 2 · Answer 2 · edited Jul 25 '20 at 19:39

2

You can use repeat + reindex:

df = df.reindex(df.index.repeat(3))
Out[105]: 
   0
0  a
0  a
0  a
1  b
1  b
1  b
2  c
2  c
2  c

Or concat:

df = pd.concat([df]*3)

edited Jul 25 '20 at 19:39

Red

answered Jul 25 '20 at 19:09

BENY

2 Answers2