在 pandas 中，如何根据一列中的唯一值创建列，然后根据另一列中的值填充它？

Question

I have an nxn column where two of columns as follows:

height  cost  item_x    cost2    item_y   weight
15      10    bat        45       mitt    2
19      12    ball       30       ball    4
24      13    gloves     25       gloves  6
22      14    bat        20       mitt    8

I want to create unique columns for unique values of item_x and item_y, and fill them with appropriate values from cost and cost2 columns. So the expected output would be:

height  bat_x  ball_x  gloves_x  mitt_y  ball_y  gloves_y   weight
15      10     0       0         45      0        0         2
19      0      12      0         0       30       0         4
24      0      0       13        0       0        25        6
22      14     0       0         20      30       0         8

Any help would be much appreciated!

Answer 1

I would do a concat on a pd.get_dummies :

# extract the suffixes `_x, _y`
suffixes = df.columns.str.extract('(_.*)$')[0]

# output
pd.concat([pd.get_dummies(df.iloc[:,i+1])
             .add_suffix(suffixes[i+1])
             .mul(df.iloc[:,i],axis=0) 
           for i in range(0,df.shape[1], 2)],
          axis=1
         )

Output:

   ball_x  bat_x  gloves_x  ball_y  gloves_y  mitt_y
0       0     10         0       0         0      45
1      12      0         0      30         0       0
2       0      0        13       0        25       0
3       0     14         0       0         0      20