Iterate DataFrame rows and add a new row right after which ever is matching

Question

I am trying to iterate a DataFrame rows with a if condition and add a new row right after whichever match the condition

for (index,row） in T.iterrows():
   if xxxx:
      ## add a new row right after current row

[Please do NOT user iterrows to iterate over a pandas dataframe.](https://stackoverflow.com/questions/16476924/how-to-iterate-over-rows-in-a-dataframe-in-pandas/55557758#55557758) — cs95, Jun 05 '19 at 13:37

score 0 · Answer 1 · answered Jun 05 '19 at 13:43

You could do it but it is slow, appreciate if anyone comes with a better solution.

    a       b
0   0.75    2.0
1   0.25    2.5
2   0.25    1.0
3   0.75    1.5
4   0.75    3.0
5   0.25    3.5

rows = []
for i, r in df.iterrows():
    rows.append(r)
    # let's b > 2 is the condition
    if r['b'] > 2:
        rows.append(pd.Series({'a': 1, 'b': 0}))
pd.DataFrame(rows).reset_index(drop=True)

    a       b
0   0.75    2.0
1   0.25    2.5
2   1.00    0.0
3   0.25    1.0
4   0.75    1.5
5   0.75    3.0
6   1.00    0.0
7   0.25    3.5
8   1.00    0.0

Iterate DataFrame rows and add a new row right after which ever is matching

1 Answers1