Pandas: Creating aggregated column in DataFrame
In [20]: df = pd.DataFrame({‘A’:[1,1,2,2],’B’:[1,2,1,2],’values’:np.arange(10,30,5)}) In [21]: df Out[21]: A B values 0 1 1 10 1 1 2 15 2 2 1 20 3 2 2 25 In [22]: df[‘sum_values_A’] = df.groupby(‘A’)[‘values’].transform(np.sum) In [23]: df Out[23]: A B values sum_values_A 0 1 1 10 25 1 1 2 15 25 2 2 1 20 … Read more