I have the following Dataframe:

Now i want to insert an empty row after every time the column "Zweck" equals 7. So for example the third row should be an empty row.

CodePudding user response：

import numpy as np
import pandas as pd

df = pd.DataFrame({'a': [1, 2, 3, 4, 5], 'b': [1, 2, 3, 4, 5], 'f': [1, 7, 3, 4, 7]})
ren_dict = {i: df.columns[i] for i in range(len(df.columns))}

ind = df[df['f'] == 7].index
df = pd.DataFrame(np.insert(df.values, ind, values=[33], axis=0))
df.rename(columns=ren_dict, inplace=True)

ind_empt = df['a'] == 33
df[ind_empt] = ''

print(df)

Output

   a  b  f
0  1  1  1
1         
2  2  2  7
3  3  3  3
4  4  4  4
5         
6  5  5  7

Here the dataframe is overwritten, as the append operation will be resource intensive. As a result, the required strings with values 33 appear. This is necessary because np.insert does not allow string values to be substituted. Columns are renamed to their original state with: df.rename. Finally, we find lines with df['a'] == 33 to set to empty values.