我们可以根据使用 python 的索引将一个数据帧中一列的值插入另一个 dataframe 的另一列吗？

Question

Sorry If my English is bad(while trying to explain). I have two different data frames. Say my df1 is,

   a  b   d   
0  1  2   5  
1  2  3   9  
2  3  4   1  
3  1  2   5  
4  2  3   9  
5  3  4   1 
6  1  2   5  
7  2  3   9  
8  3  4   1 

Second df is,

   xyz   
0  23         
1  24        
2  35     
6  17    
7  23     
8  34    

Now, I only want to replace the values in my df1(column 'a') based on the index of df2.suppose index 0 of df2 has 23 then df1 index 0 has to be changed to 23. I have tried it but I am getting an error. How do I replace the values. My code is below:-

for i in df1.index:
    for j indf2.index:
        if i == j:
            df1.iloc['a'][i] = df2.loc['xyz'][j]
            print(df1)

getting a error like

KeyError: 'xyz'

During handling of the above exception, another exception occurred:

How would I resolve this, Where am I going wrong?

Output will like this:

    a  b   d   
0  23  2   5  
1  24  3   9  
2  35  4   1  
3  1   2   5  
4  2   3   9  
5  3   4   1 
6  17  2   5  
7  23  3   9  
8  34  4   1

Answer 1

Does this help Rapooram?

df = pd.DataFrame({'a' : [1,2,3,1,2,3,1,2,3],
 'b' : [2,3,4,2,3,4,2,3,4],
 'd' : [5,9,1,5,9,1,5,9,1]})

df2 = pd.DataFrame({'index' : [0,1,2,6,7,8] ,
                   'xyz'   : [23,24,35,17,23,43]}) 

df2.set_index('index',inplace=True)


df.loc[df2.index,['a']] = df2.xyz