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delete an example from dataframe pandas python

i have a dataframe like this 

     Phrase                          Sentiment

   [ good , movie ]                   positive

   [wooow ,is , it ,very, good  ]   positive

      []                             negative
      []                              pOSTIVE

the column Phrase type is object and need to delete the rows containing [] and i don't know ho do it using python

like this:

 Phrase                          Sentiment

   [ good , movie ]                   positive

   [wooow ,is , it ,very, good  ]   positive
Solution

  • You can check the presence of empty lists by str.len()==0 and filter the DF based on this by performing a negation operation.

    df[df.Phrase.str.len() != 0]

    enter image description here

    To know the rows where empty lists are present:

    df.Phrase.str.len() == 0

0    False
1    False
2     True
3     True
Name: Phrase, dtype: bool

    Incase there are empty strings present, their length would also equate to zero. In this case, filtering on the basis of their type would be helpful by using a custom function on map.

    df[df.Phrase.map(lambda x: len(x) if isinstance(x, list) else None) != 0]

    If they are string representation of lists, then you could filter directly on them to get the subsetted DF:

    df[df.Phrase != "[]"]