CODEWITHSUNDEEP
pythonpandasdataframe
elfe
elfe

Reputation: 79

how to iteratively append multiple columns from one dataframe to another?

Lets assume 2 dataframes (float type), with same index/number of rows and dynamic number of columns, generated by some function.

    df1                       df2 
    0      avg          0      1         avg      
0   1.1    1.1      0   2.1     2.4      2.25
1   1.2    1.2      1    2.2    2.5      2.35
2   1.3   1.3       2    2.3    2.6      2.45

I would like to get from each df, all columns except the last, and append them to a new df in an iterative way.

i have tried the following

df_lst=[df1, df2]
total_df=pd.DataFrame()

for frame in df_lst:
    total_df=pd.concat(total_df, frame.iloc[:, 0:-1])

but for some reason new_df has NaN values for the last columns appended

can someone explain why is this happening? And how could i could solve it?( I have also tried with join, append, assign, but then all columns in new_df were empty)

desired output would look like

new_df
0    1.1    2.1   2.4
1    1.2    2.2   2.5
2    1.3    2.3   2.6

Upvotes: 0

Views: 477

Answers (1)

Quang Hoang
Quang Hoang

Reputation: 150745

Just add axis into concat:

df_list = [df1,df2]

pd.concat([d.iloc[:, :-1] for d in df_list], axis=1)

Output:

     0    0    1
0  1.1  2.1  2.4
1  1.2  2.2  2.5
2  1.3  2.3  2.6

Upvotes: 1

Related Questions