根据 Python 中的计数列将 DataFrame 列扩展为多行

Question

The dataframe I have:

import pandas as pd
d = pd.DataFrame({"name" : ["John", "Eric"], 
                  "days" : [1,3]})

How can I get the following data frame?

Thanks for any suggestions!

Answer 1

This for loop should suffice:

import pandas as pd

d = pd.DataFrame({"name" : ["John", "Eric"],
                  "days" : [1,3]})

for i, num in enumerate(d['days'].values):
    for j in range(num-1):
        d = d.append(d.iloc[i], ignore_index=True)

d = d.sort_values('name', ascending=False)

Output: d

   name  days
0  John     1
1  Eric     3
2  Eric     3
3  Eric     3

Explanation:

1. Iterate through values num in the column name also get the each of current row using enumerate function
2. Append current row to the Dataframe ' num-1 ' times, ignore_index argument is set to False so that the index is not duplicated
3. Use .sort_values(<column name>) to in the desired