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pythonpandasdataframeslicekeyerror

KeyError: "None of [['', '']] are in the [columns]" pandas python

I would like to slice two columns in my data frame.

This is my code for doing this:

import pandas as pd
df = pd.read_csv('source.txt',header=0)
cidf = df.loc[:,['vocab','sumCI']]

This is a sample of data:

ID  vocab   sumCI   sumnextCI   new_diff
450      statu    3.0        0.0       3.0
391     provid    4.0        1.0       3.0
382  prescript    3.0        0.0       3.0
300   lymphoma    2.0        0.0       2.0
405      renew    2.0        0.0       2.0

Firstly I got this error:

KeyError: “None of [['', '']] are in the [columns]”'

What I have tried:

  • I tried putting a header with index 0 while reading the file,
  • I tried to rename columns with this code: 
    df.rename(columns=df.iloc[0], inplace=True)
  • I also tried this: 
    df.columns = df.iloc[1]
df = df.reindex(df.index.drop(0))
  • Also tried comments in this link

None of the above resolved the issue.

Solution

  • By the print you posted, it seems like you have whitespaces as delimiters. pd.read_csv will read using , as default separator, so you have to explicitly state it:

    pd.read_csv('source.txt',header=0, delim_whitespace=True)