How to create a new dataframe column that contains rows by condition

Question

Given dataframe looking like this:

ID	ID_2	Value
12	34	100
12	56	200
12	78	300

How do we:

Filter the dataframe with ID_2 = 34/56/78
Create new columns for each of the Value

ID	New column	New column_2	New column_3
12	100	200	300

There a several ways to do this. See [link](https://stackoverflow.com/questions/26255671/pandas-column-values-to-columns) — user19077881, Feb 25 '23 at 14:22
Does this answer your question? [Pandas column values to columns?](https://stackoverflow.com/questions/26255671/pandas-column-values-to-columns) — Chris, Feb 25 '23 at 16:37

score 0 · Answer 1 · answered Feb 26 '23 at 19:33

You can do it this way:

import pandas as pd

df = pd.DataFrame({'ID': [12, 12, 12], 'ID_2': [34, 56, 78], 'Value': [100, 200, 300]})

df_filtered = df[df['ID_2'].isin([34, 56, 78])]

df_pivot = df_filtered.pivot(index='ID', columns='ID_2', values='Value')
df_pivot.columns = [f"New column_{col}" for col in df_pivot.columns]

df_pivot = df_pivot.reset_index()

print(df_pivot)

which gives

   ID  New column_34  New column_56  New column_78
0  12            100            200            300

How to create a new dataframe column that contains rows by condition

1 Answers1