Extract first and last row of a dataframe in pandas

Question

How can I extract the first and last rows of a given dataframe as a new dataframe in pandas   I ve tried to use iloc to select the desired rows and then concat as in   df pd DataFrame   a  range 1 5    b    a   b   c   d     pd concat  df iloc 0     df iloc -1        but this does not produce a pandas dataframe   a    1 b    a a    4 b    d dtype  object

User · Answer

Here is the same style as in large datasets:

x = df[:5]
y = pd.DataFrame([['...']*df.shape[1]], columns=df.columns, index=['...'])
z = df[-5:]
frame = [x, y, z]
result = pd.concat(frame)

print(result)

Output:

                     date  temp
0     1981-01-01 00:00:00  20.7
1     1981-01-02 00:00:00  17.9
2     1981-01-03 00:00:00  18.8
3     1981-01-04 00:00:00  14.6
4     1981-01-05 00:00:00  15.8
...                   ...   ...
3645  1990-12-27 00:00:00    14
3646  1990-12-28 00:00:00  13.6
3647  1990-12-29 00:00:00  13.5
3648  1990-12-30 00:00:00  15.7
3649  1990-12-31 00:00:00    13

User · Answer

I think the most simple way is  iloc  0  -1     df   pd DataFrame   a  range 1 5    b    a   b   c   d     df2   df iloc  0  -1    print df2     a  b 0  1  a 3  4  d

User · Answer

The accepted answer duplicates the first row if the frame only contains a single row  If that s a concern df 0  len df -1 if len df   gt  1  else 1  works even for single row-dataframes  Example  For the following dataframe this will not create a duplicate  df   pd DataFrame   a    1    b    a     df2   df 0  len df -1 if len df   gt  1  else 1   print df2     a  b 0  1  a  whereas this does  df3   df iloc  0  -1    print df3      a  b 0  1  a 0  1  a  because the single row is the first AND last row at the same time

User · Answer

I think you can try add parameter axis 1 to concat  because output of df iloc 0    and df iloc -1    are Series and transpose by T   print df iloc 0    a    1 b    a Name  0  dtype  object  print df iloc -1    a    4 b    d Name  3  dtype  object  print pd concat  df iloc 0     df iloc -1      axis 1     0  3 a  1  4 b  a  d  print pd concat  df iloc 0     df iloc -1      axis 1  T    a  b 0  1  a 3  4  d

User · Answer

You can also use head and tail   In  29   pd concat  df head 1   df tail 1    Out 29      a  b 0  1  a 3  4  d

[python] Extract first and last row of a dataframe in pandas

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