How to append row 2 to row 1 in pandas

Question

For example the below dataframes I have 4 rows

A    B    C
a    b    c
D    E    F
d    e    f

i would like to append row 3 to row 1, and row 4 to row 2 to form a six-column row, i.e.

A    B    C    D    E    F
a    b    c    d    e    f

How to achieve it in pandas?

@CharlieSiu Please [edit](https://stackoverflow.com/posts/46622161/edit) your question instead of adding the clarification as a comment. — ayhan, Oct 07 '17 at 16:09
@CharlieSiu, what is `A B C`? Is it a row or column names? And your desired data set - does it have two rows or one row and column names? PS i didn't downvote your question... yet... ;-) — MaxU - stand with Ukraine, Oct 07 '17 at 16:20
The best think for you to do is add the dataframe with index and column. Not just mere values.This leads to confusion. — Bharath M Shetty, Oct 07 '17 at 16:21
@CharlieSiu, and if you would have 6 rows - how many rows your desired data set would have - two? — MaxU - stand with Ukraine, Oct 07 '17 at 16:30
@CharlieSiu, IMO you should learn how to ask clear questions. [This might help...](http://stackoverflow.com/questions/20109391/how-to-make-good-reproducible-pandas-examples) — MaxU - stand with Ukraine, Oct 07 '17 at 16:36

MaxU - stand with Ukraine · Accepted Answer · 2017-10-07T16:39:42.157

UPDATE:

Source DF:

In [47]: df
Out[47]:
   0  1  2
0  A  B  C
1  a  b  c
2  D  E  F
3  d  e  f

Solution:

In [46]: pd.DataFrame(np.stack([df.iloc[::2].values.ravel(),
                                df.iloc[1::2].values.ravel()])) \
           .add_prefix('col')
Out[46]:
  col0 col1 col2 col3 col4 col5
0    A    B    C    D    E    F
1    a    b    c    d    e    f

Old answer: for the original answer, which was changed...

IIUC:

In [23]: pd.DataFrame(df.values.reshape(1,-1), columns=np.arange(1, df.size+1)) \
           .add_prefix('col')
Out[23]:
  col1 col2 col3 col4 col5 col6
0    A    B    C    D    E    F

If you have multiple rows it'll always reshape it into a single-row DF like this:

In [25]: df
Out[25]:
  col1 col2 col3
0    A    B    C
1    D    E    F
2    A    B    C
3    D    E    F

In [26]: pd.DataFrame(df.values.reshape(1,-1), columns=np.arange(1, df.size+1)) \
    ...:   .add_prefix('col')
Out[26]:
  col1 col2 col3 col4 col5 col6 col7 col8 col9 col10 col11 col12
0    A    B    C    D    E    F    A    B    C     D     E     F

or

In [33]: pd.DataFrame(df.values.reshape(-1,6), columns=np.arange(1, df.size//2+1)) \
    ...:   .add_prefix('col')
Out[33]:
  col1 col2 col3 col4 col5 col6
0    A    B    C    D    E    F
1    A    B    C    D    E    F

the question is unclear for the general case, it is best to ask the author what is what you want in the general case, could be as your comments or could only place the even rows, is ambiguous. — eyllanesc, Oct 07 '17 at 16:02
I think Op wants to make 3 column rows to 6 column rows. But dont know clearly what he meant. — Bharath M Shetty, Oct 07 '17 at 16:03

How to append row 2 to row 1 in pandas

1 Answers1