select 行来自 pandas dataframe 在另一列不同的列中具有相同值并找到平均值并使其成为字典

Question

Let's say i have a dataframe like:

     A      B     C   D
1  2010    one    0   0
2  2020    one    2   4
3  2007    two    4   8
4  2010    one    8   4
5  2020    four   6  12
6  2007    three  7  14
7  2006    four   7  14

And i want to get colum C values of the same column A values, find the average and make it a dictionary so that my output would look like:

{  "2006": 14, "2007": 11,"2010":2 .....}

What is the most practical way to solve this? I have about 10,000 rows and it doesn't make any sense of me to write them down one by one.I hope I clearly wrote about my problem.

Answer 1

Use groupby + mean to compute the mean per group and to_dict to convert to dictionary:

df.groupby('A')['C'].mean().to_dict()

output: {2006: 7.0, 2007: 5.5, 2010: 4.0, 2020: 4.0}