Python Pandas average based on condition into new column

Question

I have a pandas dataframe containing the following data:

matchID    server    court    speed
1          1         A         100
1          2         D         20         


        

Answer 1

You can get the mean by groupby and assign the values by getting the item() i.e

vals = df[df['server'].isin([1,3])].groupby(['court'])['speed'].mean().to_frame()


df['A13'],df['D13'] = vals.query("court=='A'")['speed'].item(), vals.query("court=='D'")['speed'].item()

    matchID  server court  speed    A13    D13
0         1       1     A    100  110.0  205.0
1         1       2     D    200  110.0  205.0
2         1       3     D    300  110.0  205.0
3         1       4     A    100  110.0  205.0
4         1       1     A    120  110.0  205.0
5         1       2     A    250  110.0  205.0
6         1       3     D    110  110.0  205.0
7         1       4     D    100  110.0  205.0
8         2       1     A    100  110.0  205.0
9         2       2     D    200  110.0  205.0
10        2       3     D    300  110.0  205.0
11        2       4     A    100  110.0  205.0
12        2       1     A    120  110.0  205.0
13        2       2     A    250  110.0  205.0
14        2       3     D    110  110.0  205.0
15        2       4     D    100  110.0  205.0