Fill empty fields in dataframe from a list of arrays-CodePudding

I am currently working with a dataframe, which I am creating on the fly, basically what I have so far is as follows:

  In [2]: df
  Out[2]:
     A  B  C  D
  0  1  
  1  2  
  2  3

and I have an array of data arrays in numpy as follows:

array = [[1,2,3], [4,5,6], [7,8,9]]

I have tried to fill my dataframe with this data to get the following layout:

  In [2]: df
  Out[2]:
     A  B  C  D
  0  1  1  2  3
  1  2  4  5  6
  2  3  7  8  9

What I have been trying to do is the following:

new_df = df.append({k:v for k,v in zip(list_columns,array}, ignore_index=True)

But I don't get the results I need, I don't have that much experience with pandas, is there an efficient way to do it?

Thanks in advance!

CodePudding user response：

Try this:

df[['B', 'C', 'D']] = array

Output:

>>> df
   A  B  C  D
0  1  1  2  3
1  2  4  5  6
2  3  7  8  9

That will work whether the columns were already in the dateframe or not.