63

consider a data frame defined like so:

import pandas as pd
test = pd.DataFrame({
    'id' : ['a', 'b', 'c', 'd'],
    'times' : [2, 3, 1, 5]
})

Is it possible to create a new data frame from this in which each row is repeated times times, such that the result looks like this:

>>> result
   id  times
0   a      2
1   a      2
2   b      3
3   b      3
4   b      3
5   c      1
6   d      5
7   d      5
8   d      5
9   d      5
10  d      5
Jan Trienes
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93i7hdjb
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1 Answers1

114

Use a combination of pd.DataFrame.loc and pd.Index.repeat

test.loc[test.index.repeat(test.times)]

  id  times
0  a      2
0  a      2
1  b      3
1  b      3
1  b      3
2  c      1
3  d      5
3  d      5
3  d      5
3  d      5
3  d      5

To mimic your exact output, use reset_index

test.loc[test.index.repeat(test.times)].reset_index(drop=True)

   id  times
0   a      2
1   a      2
2   b      3
3   b      3
4   b      3
5   c      1
6   d      5
7   d      5
8   d      5
9   d      5
10  d      5
piRSquared
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