Fix Python – Remove Unnamed columns in pandas dataframe [duplicate]

Question 1

I have a data file from columns A-G like below but when I am reading it with pd.read_csv('data.csv') it prints an extra unnamed column at the end for no reason.

colA    ColB    colC    colD    colE    colF    colG    Unnamed: 7
44      45      26      26      40      26      46        NaN
47      16      38      47      48      22      37        NaN
19      28      36      18      40      18      46        NaN
50      14      12      33      12      44      23        NaN
39      47      16      42      33      48      38        NaN

I have seen my data file various times but I have no extra data in any other column. How I should remove this extra column while reading ? Thanks

Question 2

df = df.loc[:, ~df.columns.str.contains('^Unnamed')]

In [162]: df
Out[162]:
   colA  ColB  colC  colD  colE  colF  colG
0    44    45    26    26    40    26    46
1    47    16    38    47    48    22    37
2    19    28    36    18    40    18    46
3    50    14    12    33    12    44    23
4    39    47    16    42    33    48    38

NOTE: very often there is only one unnamed column Unnamed: 0, which is the first column in the CSV file. This is the result of the following steps:

a DataFrame is saved into a CSV file using parameter index=True, which is the default behaviour
we read this CSV file into a DataFrame using pd.read_csv() without explicitly specifying index_col=0 (default: index_col=None)

The easiest way to get rid of this column is to specify the parameter pd.read_csv(..., index_col=0):

df = pd.read_csv('data.csv', index_col=0)

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